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Document and Entity Information - shares	6 Months Ended
Document and Entity Information - shares	Jun. 30, 2015	Jul. 23, 2015	Dec. 31, 2014
Document and Entity Information
Entity Registrant Name	COMFORT SYSTEMS USA INC
Entity Central Index Key	0001035983
Document Type	10-Q
Document Period End Date	Jun. 30, 2015
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		37,549,699
Treasury Stock, Shares	3,573,666	3,573,666	3,853,586
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q2

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
CURRENT ASSETS:
Cash and cash equivalents	$ 40,714	$ 32,064
Accounts receivable, less allowance for doubtful accounts of $4,641 and $4,379, respectively	329,338	303,575
Other receivables	6,191	15,520
Inventories	10,204	8,646
Prepaid expenses and other	26,631	25,591
Costs and estimated earnings in excess of billings	33,568	27,620
Assets related to discontinued operations	176	176
Total current assets	446,822	413,192
PROPERTY AND EQUIPMENT, NET	57,613	55,759
GOODWILL	143,569	140,341
IDENTIFIABLE INTANGIBLE ASSETS, NET	44,123	45,666
OTHER NONCURRENT ASSETS	10,922	10,792
Total assets	703,049	665,750
CURRENT LIABILITIES:
Current maturities of long-term capital lease obligations	287	317
Accounts payable	117,780	106,211
Accrued compensation and benefits	50,739	44,683
Billings in excess of costs and estimated earnings	90,322	77,446
Accrued self-insurance expense	29,738	28,903
Other current liabilities	35,332	24,814
Liabilities related to discontinued operations	263	263
Total current liabilities	324,461	282,637
LONG-TERM DEBT	19,000	39,500
LONG-TERM CAPITAL LEASE OBLIGATIONS	396	529
DEFERRED INCOME TAX LIABILITIES	9,841	10,817
OTHER LONG-TERM LIABILITIES	7,838	10,874
Total liabilities	361,536	344,357
COMMITMENTS AND CONTINGENCIES
STOCKHOLDERS' EQUITY:
Preferred stock, $.01 par, 5,000,000 shares authorized, none issued and outstanding
Common stock, $.01 par, 102,969,912 shares authorized, 41,123,365 and 41,123,365 shares issued, respectively	411	411
Treasury stock, at cost, 3,573,666 and 3,853,586 shares, respectively	(41,486)	(43,598)
Additional paid-in capital	322,015	320,084
Retained earnings	43,375	29,384
Comfort Systems USA, Inc. stockholders' equity	324,315	306,281
Noncontrolling interests	17,198	15,112
Total stockholders' equity	341,513	321,393
Total liabilities and stockholders' equity	$ 703,049	$ 665,750

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
CONSOLIDATED BALANCE SHEETS
Accounts receivable, allowance for doubtful accounts (in dollars)	$ 4,641	$ 4,379
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	102,969,912	102,969,912
Common stock, shares issued	41,123,365	41,123,365
Treasury stock, shares	3,573,666	3,853,586

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
CONSOLIDATED STATEMENTS OF OPERATIONS
REVENUE	$ 416,567	$ 362,801	$ 786,114	$ 684,182
COST OF SERVICES	334,518	300,942	639,377	570,174
Gross profit	82,049	61,859	146,737	114,008
SELLING, GENERAL AND ADMINISTRATIVE EXPENSES	57,369	50,573	111,065	100,958
GOODWILL IMPAIRMENT		727		727
GAIN ON SALE OF ASSETS	(151)	(89)	(327)	(222)
Operating income	24,831	10,648	35,999	12,545
OTHER INCOME (EXPENSE):
Interest income	67	2	68	13
Interest expense	(454)	(462)	(959)	(798)
Changes in the fair value of contingent earn-out obligations	125	(130)	125
Other	9	24	27	92
Other income (expense)	(253)	(566)	(739)	(693)
INCOME BEFORE INCOME TAXES	24,578	10,082	35,260	11,852
INCOME TAX EXPENSE	8,796	3,746	12,589	4,438
INCOME FROM CONTINUING OPERATIONS	15,782	6,336	22,671	7,414
Loss from discontinued operations, net of income tax benefit of $-, $-, $- and $10				(15)
NET INCOME INCLUDING NONCONTROLLING INTERESTS	15,782	6,336	22,671	7,399
Less: Net income (loss) attributable to noncontrolling interests	2,378	1,935	4,201	2,623
NET INCOME ATTRIBUTABLE TO COMFORT SYSTEMS USA, INC.	$ 13,404	$ 4,401	$ 18,470	$ 4,776
Basic-
Income from continuing operations (in dollars per share)	$ 0.36	$ 0.12	$ 0.49	$ 0.13
Net income (in dollars per share)	0.36	0.12	0.49	0.13
Diluted-
Income from continuing operations (in dollars per share)	0.35	0.12	0.49	0.13
Net income (in dollars per share)	$ 0.35	$ 0.12	$ 0.49	$ 0.13
SHARES USED IN COMPUTING INCOME PER SHARE:
Basic (in shares)	37,457,000	37,706,000	37,370,000	37,644,000
Diluted (in shares)	37,917,000	37,880,000	37,761,000	37,914,000
DIVIDENDS PER SHARE (in dollars per share)	$ 0.060	$ 0.055	$ 0.120	$ 0.110

CONSOLIDATED STATEMENTS OF OPERATIONS (Parenthetical) $ in Thousands	6 Months Ended
	Jun. 30, 2014 USD ($)
CONSOLIDATED STATEMENTS OF OPERATIONS
Operating loss, income tax expense (benefit)	$ 10

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Common Stock	Treasury Stock	Additional Paid-In Capital	Retained Earnings	Non-Controlling Interests	Total
BALANCE at Dec. 31, 2013	$ 411	$ (37,468)	$ 318,123	$ 14,768	$ 18,188	$ 314,022
BALANCE (in shares) at Dec. 31, 2013	41,123,365
BALANCE (in shares) at Dec. 31, 2013		(3,488,438)
Increase (Decrease) in Stockholders' Equity
Net income				23,063	5,536	28,599
Issuance of Stock:
Issuance of shares for options exercised including tax benefit		$ 1,132	79			1,211
Issuance of shares for options exercised including tax benefit (in shares)		103,619
Issuance of restricted stock & performance stock		$ 1,243	(1,243)
Issuance of restricted stock & performance stock (in shares)		115,044
Shares received in lieu of tax withholding payment on vested restricted stock		$ (531)				(531)
Shares received in lieu of tax withholding payment on vested restricted stock (in shares)		(34,657)
Tax benefit from vesting of restricted stock			133			133
Stock-based compensation expense			2,992			2,992
Dividends				(8,447)		(8,447)
Distribution to noncontrolling interests (unaudited)					(8,612)	(8,612)
Share repurchase		$ (7,974)				(7,974)
Share repurchase (in shares)		(549,154)
BALANCE at Dec. 31, 2014	$ 411	$ (43,598)	320,084	29,384	15,112	$ 321,393
BALANCE (in shares) at Dec. 31, 2014	41,123,365					41,123,365
BALANCE (in shares) at Dec. 31, 2014		(3,853,586)				3,853,586
Increase (Decrease) in Stockholders' Equity
Net income				18,470	4,201	$ 22,671
Issuance of Stock:
Issuance of shares for options exercised including tax benefit		$ 2,282	195			2,477
Issuance of shares for options exercised including tax benefit (in shares)		197,528
Issuance of restricted stock & performance stock		$ 2,292	(626)			1,666
Issuance of restricted stock & performance stock (in shares)		200,015
Shares received in lieu of tax withholding payment on vested restricted stock		$ (937)				(937)
Shares received in lieu of tax withholding payment on vested restricted stock (in shares)		(44,590)
Tax benefit from vesting of restricted stock			261			261
Stock-based compensation expense			2,101			2,101
Dividends				(4,479)		(4,479)
Distribution to noncontrolling interests (unaudited)					(2,115)	(2,115)
Share repurchase		$ (1,525)				$ (1,525)
Share repurchase (in shares)		(73,033)				(100,000)
BALANCE at Jun. 30, 2015	$ 411	$ (41,486)	$ 322,015	$ 43,375	$ 17,198	$ 341,513
BALANCE (in shares) at Jun. 30, 2015	41,123,365					41,123,365
BALANCE (in shares) at Jun. 30, 2015		(3,573,666)				3,573,666

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
CASH FLOWS FROM OPERATING ACTIVITIES
Net income including noncontrolling interests	$ 15,782	$ 6,336	$ 22,671	$ 7,399
Adjustments to reconcile net income to net cash provided by (used in) operating activities-
Amortization of identifiable intangible assets	1,893	1,781	3,724	3,385
Depreciation expense	3,948	3,219	7,740	6,269
Goodwill impairment		727		727
Bad debt expense	683	202	894	235
Deferred tax expense (benefit)	(1,022)	(1)	(2,263)	(1,623)
Amortization of debt financing costs	65	65	158	130
Gain on sale of assets	(151)	(89)	(327)	(222)
Changes in the fair value of contingent earn-out obligations	(125)	130	(125)
Stock-based compensation expense	1,790	1,439	3,178	2,870
(Increase) decrease in-
Receivables, net	(20,845)	(7,805)	(17,991)	(475)
Inventories	(177)	135	(1,440)	(258)
Prepaid expenses and other current assets	1,071	827	1,806	1,651
Costs and estimated earnings in excess of billings	(2,268)	(3,816)	(5,860)	(8,259)
Other noncurrent assets	(493)	(84)	(215)	98
Increase (decrease) in-
Accounts payable and accrued liabilities	22,237	9,167	25,958	(2,002)
Billings in excess of costs and estimated earnings	8,016	10,054	12,833	3,873
Other long-term liabilities	(159)	98	(81)	(197)
Net cash provided by operating activities	30,245	22,385	50,660	13,601
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of property and equipment	(5,685)	(4,452)	(9,308)	(8,334)
Proceeds from sales of property and equipment	279	323	485	540
Cash paid for acquisitions, net of cash acquired	(511)	(47,359)	(5,861)	(51,359)
Net cash used in investing activities	(5,917)	(51,488)	(14,684)	(59,153)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from revolving line of credit		83,500	14,500	101,500
Payment on revolving line of credit	(18,000)	(38,500)	(35,000)	(49,500)
Payments on other long-term debt		(2,000)		(2,000)
Payments on capital lease obligations	(79)		(163)
Payments of dividends to shareholders	(2,242)	(2,072)	(4,479)	(4,139)
Share repurchase program	(1,525)	(89)	(1,525)	(505)
Shares received in lieu of tax withholding	(937)	(531)	(937)	(531)
Excess tax benefit of stock-based compensation	371	119	461	105
Proceeds from exercise of options	1,980	284	2,277	826
Distributions to noncontrolling interests	(2,074)	(2,499)	(2,115)	(2,499)
Payments for contingent consideration arrangements			(345)
Net cash provided by (used in) financing activities	(22,506)	38,212	(27,326)	43,257
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	1,822	9,109	8,650	(2,295)
CASH AND CASH EQUIVALENTS, beginning of period	38,892	40,650	32,064	52,054
CASH AND CASH EQUIVALENTS, end of period	$ 40,714	$ 49,759	$ 40,714	$ 49,759

Business and Organization	6 Months Ended
Business and Organization	Jun. 30, 2015
Business and Organization
Business and Organization	1. Business and Organization Comfort Systems USA, Inc., a Delaware corporation, provides comprehensive heating, ventilation and air conditioning ("HVAC") installation, maintenance, repair and replacement services within the mechanical services industry. We operate primarily in the commercial, industrial and institutional HVAC markets and perform most of our services within office buildings, retail centers, apartment complexes, manufacturing plants and healthcare, education and government facilities. In addition to standard HVAC services, we provide specialized applications such as building automation control systems, fire protection, process cooling, electronic monitoring and process piping. Certain locations also perform related activities such as electrical service and plumbing. Approximately 48% of our consolidated 2015 revenue was attributable to installation of systems in newly constructed facilities, with the remaining 52% attributable to maintenance, repair and replacement services. The following service activities account for our consolidated 2015 revenue: HVAC 77%, plumbing 15%, building automation control systems 5% and other 3%. These service activities are within the mechanical services industry, which is the single industry segment we serve.

Summary of Significant Accounting Policies	6 Months Ended
Summary of Significant Accounting Policies	Jun. 30, 2015
Summary of Significant Accounting Policies
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies Basis of Presentation These interim statements should be read in conjunction with the historical Consolidated Financial Statements and related notes of Comfort Systems included in the Annual Report on Form 10-K as filed with the Securities and Exchange Commission ("SEC") for the year ended December 31, 2014 (the "Form 10-K"). The accompanying unaudited consolidated financial statements were prepared using generally accepted accounting principles for interim financial information and the instructions to Form 10-Q and applicable rules of Regulation S-X of the SEC. Accordingly, these financial statements do not include all the footnotes required by generally accepted accounting principles for complete financial statements and should be read in conjunction with the Form 10-K. We believe all adjustments necessary for a fair presentation of these interim statements have been included and are of a normal and recurring nature. Certain amounts in prior periods may have been reclassified to conform to the current year presentation. The effects of the reclassifications were not material to the unaudited consolidated financial statements. The results of operations for interim periods are not necessarily indicative of the results for the full fiscal year. Use of Estimates The preparation of financial statements in conformity with generally accepted accounting principles requires the use of estimates and assumptions by management in determining the reported amounts of assets and liabilities, revenue and expenses and disclosures regarding contingent assets and liabilities. Actual results could differ from those estimates. The most significant estimates used in our financial statements affect revenue and cost recognition for construction contracts, the allowance for doubtful accounts, self-insurance accruals, deferred tax assets, warranty accruals, fair value accounting for acquisitions and the quantification of fair value for reporting units in connection with our goodwill impairment testing. Recent Accounting Pronouncements In May 2014, the FASB issued ASU No. 2014-09, "Revenue from Contracts with Customers (Topic 606)." ASU 2014-09 provides a framework that replaces the existing revenue recognition guidance. The guidance can be applied on a full retrospective or modified retrospective basis whereby the entity records a cumulative effect of initially applying this update at the date of initial application. It is effective for annual periods beginning after December 15, 2017, including interim periods within that reporting period. We are currently evaluating the potential impact of this authoritative guidance on our consolidated financial statements. In April 2015, the FASB issued ASU No. 2015-03, "Simplifying the Presentation of Debt Issue Costs." Under ASU 2015-03, an entity presents debt issue costs related to a note in the balance sheet as a direct deduction from the related debt liability rather than as an asset. Entities would apply the new guidance retrospectively to all prior periods. ASU No. 2015-03 does not address the presentation of issuance costs associated with revolving debt agreements. It is effective for annual periods beginning after December 15, 2015, including interim periods within that reporting period. Currently, this authoritative guidance is not expected to have a material impact on our consolidated financial statements. In July 2015, the FASB issued ASU No. 2015-11, "Simplifying the Measurement of Inventory", which requires that inventory within the scope of the guidance be measured at the lower of cost and net realizable value. Net realizable value is the estimated selling prices in the ordinary course of business, less reasonable predictable costs of completion, disposal and transportation. Inventory measured using last-in, first-out (LIFO) and the retail inventory method (RIM) are not impacted by the new guidance. Entities should apply the new guidance prospectively with earlier application permitted as of the beginning of an interim or annual reporting period. It is effective for fiscal years beginning after December 15, 2016, including interim periods within those fiscal years. We are currently evaluating the potential impact of this authoritative guidance on our consolidated financial statements. Financial Instruments Our financial instruments consist of cash and cash equivalents, accounts receivable, other receivables, accounts payable, life insurance policies, notes to former owners, capital leases and a revolving credit facility. We believe that the carrying values of these instruments on the accompanying balance sheets approximate their fair values. Segment Disclosure Our activities are within the mechanical services industry, which is the single industry segment we serve. Each operating subsidiary represents an operating segment and these segments have been aggregated, as the operating units meet all of the aggregation criteria.

Fair Value Measurements

6 Months Ended

Jun. 30, 2015

Fair Value Measurements

Fair Value Measurements

3. Fair Value Measurements

We classify and disclose assets and liabilities carried at fair value in one of the following three categories:


	•	Level 1—quoted prices in active markets for identical assets and liabilities;
	•	Level 2—observable market based inputs or unobservable inputs that are corroborated by market data; and
	•	Level 3—significant unobservable inputs in which little or no market data exists, therefore requiring an entity to develop its own assumptions.

The following table summarizes the fair values and levels within the fair value hierarchy in which the fair value measurements fall for assets and liabilities measured on a recurring basis as of June 30, 2015 (in thousands):

			Fair Value Measurements at Reporting Date Using
	Total		Quoted Prices In Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Cash and cash equivalents	$	40,714	$	40,714	$	—	$	—
Life insurance—cash surrender value	$	3,397	$	—	$	3,397	$	—
Contingent earn-out obligations	$	300	$	—	$	—	$	300

Cash and cash equivalents consist primarily of highly rated money market funds at a variety of well-known institutions with original maturities of three months or less. The original cost of these assets approximates fair value due to their short term maturity.

One of our operations has life insurance policies covering 46 employees with a combined face value of $42.6 million. The policy is invested in mutual funds and the fair value measurement of the cash surrender balance associated with these policies is determined using Level 2 inputs within the fair value hierarchy and will vary with investment performance. The cash surrender value of these policies was $3.4 million as of June 30, 2015. These assets are included in "Other Noncurrent Assets" in our consolidated balance sheets.

We value contingent earn-out obligations using a probability weighted discounted cash flow method. This fair value measurement is based on significant unobservable inputs in the market and thus represents a Level 3 measurement within the fair value hierarchy. This analysis reflects the contractual terms of the purchase agreements (e.g., minimum and maximum payments, length of earn-out periods, manner of calculating any amounts due, etc.) and utilizes assumptions with regard to future cash flows, probabilities of achieving such future cash flows and a discount rate. The contingent earn-out obligations are measured at fair value each reporting period and changes in estimates of fair value are recognized in earnings.

The table below presents a reconciliation of the fair value of our contingent earn-out obligations that use significant unobservable inputs (Level 3) (in thousands):

Balance at beginning of year	$	670
Issuances		100
Settlements		(345	)
Adjustments to fair value		(125	)

Balance at end of period	$	300

We measure certain assets at fair value on a nonrecurring basis. These assets are recognized at fair value when they are deemed to be other-than-temporarily impaired. During the quarter ended June 30, 2014, we recorded a goodwill impairment charge of $0.7 million based on Level 3 measurements. We did not recognize any impairments, in the current year, on those assets required to be measured at fair value on a nonrecurring basis.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Acquisitions	6 Months Ended
Acquisitions	Jun. 30, 2015
Acquisitions
Acquisitions	4. Acquisitions Acquisition of DynaTen On May 1, 2014, we closed a transaction to acquire DynaTen Corporation ("DynaTen") which reports as a separate operating location in Northern Texas. DynaTen is a regional mechanical contractor based in Fort Worth, Texas which engages in a broad range of mechanical contracting projects, HVAC services and controls, in the Dallas/Fort Worth metroplex and in surrounding areas. The total purchase price, which was finalized in the first quarter of 2015 was $40.5 million, of which $19.8 million was allocated to goodwill. Other Acquisitions We completed two acquisitions in the first quarter of 2015. In addition to the DynaTen acquisition noted above, additional acquisitions were completed in the first and second quarter of 2014. These acquisitions were not material and were "tucked-in" with existing operations. The total purchase price for the "tucked-in" acquisitions, including earn-outs, was $6.7 million and $9.5 million for the six months ended June 30, 2015 and 2014, respectively. Our consolidated balance sheet includes preliminary allocations of the purchase price, related to the two acquisitions completed in the fiscal year 2015, to the assets acquired and liabilities assumed based on estimates of fair value, pending completion of final valuation and purchase price adjustments. The results of operations of acquisitions are included in our consolidated financial statements from their respective acquisition dates. Additional contingent purchase price ("earn-out") has been or will be paid if certain acquisitions achieve predetermined profitability targets.

- Definition

The entire disclosure for a business combination (or series of individually immaterial business combinations) completed during the period, including background, timing, and recognized assets and liabilities. The disclosure may include leverage buyout transactions (as applicable).

+ References

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-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6996-128479

+ Details

Goodwill

6 Months Ended

Jun. 30, 2015

Goodwill

Goodwill

5. Goodwill

The changes in the carrying amount of goodwill are as follows (in thousands):

	June 30, 2015		December 31, 2014
Balance at beginning of year	$	140,341	$	114,588
Additions		3,228		26,480
Impairment adjustment		—		(727	)

Balance at end of period	$	143,569	$	140,341

- Definition

The entire disclosure for the aggregate amount of goodwill and a description of intangible assets, which may include (a) for amortizable intangible assets (also referred to as finite-lived intangible assets), the carrying amount, the amount of any significant residual value, and the weighted-average amortization period, (b) for intangible assets not subject to amortization (also referred to as indefinite-lived intangible assets), the carrying amount, and (c) the amount of research and development assets acquired and written off in the period, including the line item in the income statement in which the amounts written off are aggregated, if not readily apparent from the income statement. Also discloses (a) for amortizable intangibles assets in total and by major class, the gross carrying amount and accumulated amortization, the total amortization expense for the period, and the estimated aggregate amortization expense for each of the five succeeding fiscal years, (b) for intangible assets not subject to amortization the carrying amount in total and by major class, and (c) for goodwill, in total and for each reportable segment, the changes in the carrying amount of goodwill during the period (including the aggregate amount of goodwill acquired, the aggregate amount of impairment losses recognized, and the amount of goodwill included in the gain (loss) on disposal of a reporting unit). If any part of goodwill has not been allocated to a reportable segment, discloses the unallocated amount and the reasons for not allocating. For each impairment loss recognized related to an intangible asset (excluding goodwill), discloses: (a) a description of the impaired intangible asset and the facts and circumstances leading to the impairment, (b) the amount of the impairment loss and the method for determining fair value, (c) the caption in the income statement or the statement of activities in which the impairment loss is aggregated, and (d) the segment in which the impaired intangible asset is reported. For each goodwill impairment loss recognized, discloses: (a) a description of the facts and circumstances leading to the impairment, (b) the amount of the impairment loss and the method of determining the fair value of the associated reporting unit, and (c) if a recognized impairment loss is an estimate not finalized and the reasons why the estimate is not final. May also disclose the nature and amount of any significant adjustments made to a previous estimate of an impairment loss.

+ References + Details

Long-Term Debt Obligations

6 Months Ended

Jun. 30, 2015

Long-Term Debt Obligations

Long-Term Debt Obligations

6. Long-Term Debt Obligations

Long-term debt obligations consist of the following (in thousands):

	June 30, 2015			December 31, 2014
Revolving credit facility	$	18,000		$	38,500
Notes to former owners		1,000			1,000
Capital lease obligations		683			846

Total debt		19,683			40,346
Less—current portion		(287	)		(317	)

Total long-term portion of debt	$	19,396		$	40,029

Revolving Credit Facility

We have a $250.0 million senior credit facility (the "Facility") provided by a syndicate of banks which is available for borrowings and letters of credit. The Facility expires in October 2019 and is secured by a first lien on substantially all of our personal property, except for assets related to projects subject to surety bonds and assets held by certain unrestricted subsidiaries, and a second lien on our assets related to projects subject to surety bonds. As of June 30, 2015, we had $18.0 million of outstanding borrowings, $48.0 million in letters of credit outstanding and $184.0 million of credit available.

There are two interest rate options for borrowings under the Facility, the Base Rate Loan Option and the Eurodollar Rate Loan Option. These rates are floating rates determined by the broad financial markets, meaning they can and do move up and down from time to time. Additional margins are then added to these two rates.

The following is a summary of the additional margins:

	Consolidated Total Indebtedness to Credit Facility Adjusted EBITDA
	Less than 0.75			0.75 to 1.50			1.50 to 2.25			2.25 or greater
Additional Per Annum Interest Margin Added Under:
Base Rate Loan Option		0.25	%		0.50	%		0.75	%		1.00	%
Eurodollar Rate Loan Option		1.25	%		1.50	%		1.75	%		2.00	%

The weighted average interest rate applicable to the borrowings under the Facility was approximately 1.4% as of June 30, 2015.

Certain of our vendors require letters of credit to ensure reimbursement for amounts they are disbursing on our behalf, such as to beneficiaries under our self-funded insurance programs. We have also occasionally used letters of credit to guarantee performance under our contracts and to ensure payment to our subcontractors and vendors under those contracts. Our lenders issue such letters of credit through the Facility for a fee. We have never had a claim made against a letter of credit that resulted in payments by a lender or by us and believe such claim is unlikely in the foreseeable future. The letter of credit fees range from 1.25% to 2.00% per annum, based on the ratio of Consolidated Total Indebtedness to Credit Facility Adjusted EBITDA, as defined in the credit agreement.

Commitment fees are payable on the portion of the revolving loan capacity not in use for borrowings or letters of credit at any given time. These fees range from 0.20% to 0.35% per annum, based on the ratio of Consolidated Total Indebtedness to Credit Facility Adjusted EBITDA, as defined in the credit agreement.

The Facility contains financial covenants defining various financial measures and the levels of these measures with which we must comply. Covenant compliance is assessed as of each quarter end.

The Facility's principal financial covenants include:

Leverage Ratio—The Facility requires that the ratio of our Consolidated Total Indebtedness to our Credit Facility Adjusted EBITDA not exceed 2.75 through maturity. The leverage ratio as of June 30, 2015 was 0.23.

Fixed Charge Coverage Ratio—The Facility requires that the ratio of Credit Facility Adjusted EBITDA, less non-financed capital expenditures, tax provision, dividends and amounts used to repurchase stock to the sum of interest expense and scheduled principal payments of indebtedness be at least 2.00; provided that the calculation of the fixed charge coverage ratio excludes stock repurchases and the payment of dividends at any time that the Company's Net Leverage Ratio does not exceed 1.50. The Facility also allows the fixed charge coverage ratio not to be reduced for stock repurchases through September 30, 2015 in an aggregate amount not to exceed $25 million if at the time of and after giving effect to such repurchase the Company's Net Leverage Ratio was less than or equal to 1.50. Capital expenditures, tax provision, dividends and stock repurchase payments are defined under the Facility for purposes of this covenant to be amounts for the four quarters ending as of any given quarterly covenant compliance measurement date. The fixed charge coverage ratio as of June 30, 2015 was 24.05.

Other Restrictions—The Facility permits acquisitions of up to $25.0 million per transaction, provided that the aggregate purchase price of such an acquisition and of acquisitions in the same fiscal year does not exceed $60.0 million. However, these limitations only apply when the Company's Net Leverage Ratio is equal to or greater than 2.00.

While the Facility's financial covenants do not specifically govern capacity under the Facility, if our debt level under the Facility at a quarter-end covenant compliance measurement date were to cause us to violate the Facility's leverage ratio covenant, our borrowing capacity under the Facility and the favorable terms that we currently have could be negatively impacted by the lenders.

We were in compliance with all of our financial covenants as of June 30, 2015.

Notes to Former Owners

We issued a subordinated note to the former owners of an acquired company as part of the consideration used to acquire the company. This note had an outstanding balance of $1.0 million as of June 30, 2015 and bears interest, payable quarterly, at a weighted average interest rate of 2.5%. The principle is due in equal installments on October 2016 and 2017.

Other Debt

In conjunction with our acquisition of our northern Texas operation, we acquired capital lease obligations of $0.7 million. Currently, $0.7 million of capital lease obligations are outstanding, of which $0.3 million is considered current.

Our majority owned subsidiary, Environmental Air Systems, LLC, has a revolving $2.5 million credit line that is available for temporary working capital needs and expires May 31, 2016. As of June 30, 2015, we had no outstanding borrowings and, therefore, $2.5 million of credit available. We estimate that the weighted average interest rate applicable to borrowings under this variable rate credit line would be approximately 2.0% as of June 30, 2015.

Commitments and Contingencies	6 Months Ended
Commitments and Contingencies	Jun. 30, 2015
Commitments and Contingencies
Commitments and Contingencies	7. Commitments and Contingencies Claims and Lawsuits We are subject to certain legal and regulatory claims, including lawsuits arising in the normal course of business. We maintain various insurance coverages to minimize financial risk associated with these claims. We have estimated and provided accruals for probable losses and related legal fees associated with certain litigation in the accompanying consolidated financial statements. While we cannot predict the outcome of these proceedings, in management's opinion and based on reports of counsel, any liability arising from these matters individually and in the aggregate will not have a material effect on our operating results, cash flows or financial condition, after giving effect to provisions already recorded. Surety Many customers, particularly in connection with new construction, require us to post performance and payment bonds issued by a financial institution known as a surety. If we fail to perform under the terms of a contract or to pay subcontractors and vendors who provided goods or services under a contract, the customer may demand that the surety make payments or provide services under the bond. We must reimburse the surety for any expenses or outlays it incurs. To date, we are not aware of any losses to our sureties in connection with bonds the sureties have posted on our behalf, and do not expect such losses to be incurred in the foreseeable future. Surety market conditions have seen some strengthening as the commercial construction markets have started to rebound. Bonding capacity remains adequate in the current market conditions along with acceptable terms and conditions. Historically, approximately 25% to 35% of our business has required bonds. While we currently have strong surety relationships to support our bonding needs, future market conditions or changes in the sureties' assessment of our operating and financial risk could cause the sureties to decline to issue bonds for our work. If that were to occur, the alternatives include doing more business that does not require bonds, posting other forms of collateral for project performance such as letters of credit or cash, and seeking bonding capacity from other sureties. We would likely also encounter concerns from customers, suppliers and other market participants as to our creditworthiness. While we believe our general operating and financial characteristics would enable us to ultimately respond effectively to an interruption in the availability of bonding capacity, such an interruption would likely cause our revenue and profits to decline in the near term. Self-Insurance We are substantially self-insured for workers' compensation, employer's liability, auto liability, general liability and employee group health claims, in view of the relatively high per-incident deductibles we absorb under our insurance arrangements for these risks. Losses up to deductible amounts are estimated and accrued based upon known facts, historical trends and industry averages. Loss estimates associated with the larger and longer-developing risks, such as workers' compensation, auto liability and general liability, are reviewed by a third-party actuary quarterly.

Stockholders' Equity

6 Months Ended

Jun. 30, 2015

Stockholders' Equity

Stockholders' Equity

8. Stockholders' Equity

Earnings Per Share

Basic earnings per share ("EPS") is computed by dividing net income by the weighted average number of shares of common stock outstanding during the period. Diluted EPS is computed considering the dilutive effect of stock options, contingently issuable restricted stock and restricted stock units.

There were no anti-dilutive stock options for the three and six months ended June 30, 2015, respectively. There were no anti-dilutive stock options for the six months ended June 30, 2014. There were approximately 0.2 million anti-dilutive stock options excluded from the calculation of diluted EPS for the three months ended June 30, 2014.

The following table reconciles the number of shares outstanding with the number of shares used in computing basic and diluted earnings per share for each of the periods presented (in thousands):

	Three Months Ended June 30,						Six Months Ended June 30,
	2015			2014			2015			2014
Common shares outstanding, end of period		37,550			37,748			37,550			37,748
Effect of using weighted average common shares outstanding		(93	)		(42	)		(180	)		(104	)

Shares used in computing earnings per share—basic		37,457			37,706			37,370			37,644
Effect of shares issuable under stock option plans based on the treasury stock method		289			144			260			165
Effect of restricted shares		171			30			131			105

Shares used in computing earnings per share—diluted		37,917			37,880			37,761			37,914

Share Repurchase Program

On March 29, 2007, our Board of Directors (the "Board") approved a stock repurchase program to acquire up to 1.0 million shares of our outstanding common stock. Subsequently, the Board has from time to time approved extensions of the program to acquire additional shares. Since the inception of the repurchase program, the Board has approved 7.6 million shares to be repurchased.

The share repurchases will be made from time to time at our discretion in the open market or privately negotiated transactions as permitted by securities laws and other legal requirements, and subject to market conditions and other factors. The Board may modify, suspend, extend or terminate the program at any time. During the six months ended June 30, 2015, we repurchased 0.1 million shares for approximately $1.5 million at an average price of $20.88 per share. Since the inception of the program in 2007 through June 30, 2015, we have repurchased a cumulative total of 6.6 million shares at an average price of $11.40 per share.

Summary of Significant Accounting Policies (Policies)	6 Months Ended
Summary of Significant Accounting Policies (Policies)	Jun. 30, 2015
Summary of Significant Accounting Policies
Basis of Presentation	Basis of Presentation These interim statements should be read in conjunction with the historical Consolidated Financial Statements and related notes of Comfort Systems included in the Annual Report on Form 10-K as filed with the Securities and Exchange Commission ("SEC") for the year ended December 31, 2014 (the "Form 10-K"). The accompanying unaudited consolidated financial statements were prepared using generally accepted accounting principles for interim financial information and the instructions to Form 10-Q and applicable rules of Regulation S-X of the SEC. Accordingly, these financial statements do not include all the footnotes required by generally accepted accounting principles for complete financial statements and should be read in conjunction with the Form 10-K. We believe all adjustments necessary for a fair presentation of these interim statements have been included and are of a normal and recurring nature. Certain amounts in prior periods may have been reclassified to conform to the current year presentation. The effects of the reclassifications were not material to the unaudited consolidated financial statements. The results of operations for interim periods are not necessarily indicative of the results for the full fiscal year.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with generally accepted accounting principles requires the use of estimates and assumptions by management in determining the reported amounts of assets and liabilities, revenue and expenses and disclosures regarding contingent assets and liabilities. Actual results could differ from those estimates. The most significant estimates used in our financial statements affect revenue and cost recognition for construction contracts, the allowance for doubtful accounts, self-insurance accruals, deferred tax assets, warranty accruals, fair value accounting for acquisitions and the quantification of fair value for reporting units in connection with our goodwill impairment testing.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In May 2014, the FASB issued ASU No. 2014-09, "Revenue from Contracts with Customers (Topic 606)." ASU 2014-09 provides a framework that replaces the existing revenue recognition guidance. The guidance can be applied on a full retrospective or modified retrospective basis whereby the entity records a cumulative effect of initially applying this update at the date of initial application. It is effective for annual periods beginning after December 15, 2017, including interim periods within that reporting period. We are currently evaluating the potential impact of this authoritative guidance on our consolidated financial statements. In April 2015, the FASB issued ASU No. 2015-03, "Simplifying the Presentation of Debt Issue Costs." Under ASU 2015-03, an entity presents debt issue costs related to a note in the balance sheet as a direct deduction from the related debt liability rather than as an asset. Entities would apply the new guidance retrospectively to all prior periods. ASU No. 2015-03 does not address the presentation of issuance costs associated with revolving debt agreements. It is effective for annual periods beginning after December 15, 2015, including interim periods within that reporting period. Currently, this authoritative guidance is not expected to have a material impact on our consolidated financial statements. In July 2015, the FASB issued ASU No. 2015-11, "Simplifying the Measurement of Inventory", which requires that inventory within the scope of the guidance be measured at the lower of cost and net realizable value. Net realizable value is the estimated selling prices in the ordinary course of business, less reasonable predictable costs of completion, disposal and transportation. Inventory measured using last-in, first-out (LIFO) and the retail inventory method (RIM) are not impacted by the new guidance. Entities should apply the new guidance prospectively with earlier application permitted as of the beginning of an interim or annual reporting period. It is effective for fiscal years beginning after December 15, 2016, including interim periods within those fiscal years. We are currently evaluating the potential impact of this authoritative guidance on our consolidated financial statements.
Financial Instruments	Financial Instruments Our financial instruments consist of cash and cash equivalents, accounts receivable, other receivables, accounts payable, life insurance policies, notes to former owners, capital leases and a revolving credit facility. We believe that the carrying values of these instruments on the accompanying balance sheets approximate their fair values.
Segment Disclosure	Segment Disclosure Our activities are within the mechanical services industry, which is the single industry segment we serve. Each operating subsidiary represents an operating segment and these segments have been aggregated, as the operating units meet all of the aggregation criteria.

Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2015

Fair Value Measurements

Summary of fair values and levels within the fair value hierarchy in which the fair value measurements fall for assets and liabilities measured on a recurring basis

			Fair Value Measurements at Reporting Date Using
	Total		Quoted Prices In Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Cash and cash equivalents	$	40,714	$	40,714	$	—	$	—
Life insurance—cash surrender value	$	3,397	$	—	$	3,397	$	—
Contingent earn-out obligations	$	300	$	—	$	—	$	300

Schedule of reconciliation of the fair value of contingent earn-out obligations that use significant unobservable inputs (Level 3)

The table below presents a reconciliation of the fair value of our contingent earn-out obligations that use significant unobservable inputs (Level 3) (in thousands):

Balance at beginning of year	$	670
Issuances		100
Settlements		(345	)
Adjustments to fair value		(125	)

Balance at end of period	$	300

Goodwill (Tables)

6 Months Ended

Jun. 30, 2015

Goodwill

Schedule of changes in the carrying amount of goodwill

The changes in the carrying amount of goodwill are as follows (in thousands):

	June 30, 2015		December 31, 2014
Balance at beginning of year	$	140,341	$	114,588
Additions		3,228		26,480
Impairment adjustment		—		(727	)

Balance at end of period	$	143,569	$	140,341

Long-Term Debt Obligations (Tables)

6 Months Ended

Jun. 30, 2015

Long-Term Debt Obligations

Schedule of components of long-term debt obligations

Long-term debt obligations consist of the following (in thousands):

	June 30, 2015			December 31, 2014
Revolving credit facility	$	18,000		$	38,500
Notes to former owners		1,000			1,000
Capital lease obligations		683			846

Total debt		19,683			40,346
Less—current portion		(287	)		(317	)

Total long-term portion of debt	$	19,396		$	40,029

Summary of additional margins

	Consolidated Total Indebtedness to Credit Facility Adjusted EBITDA
	Less than 0.75			0.75 to 1.50			1.50 to 2.25			2.25 or greater
Additional Per Annum Interest Margin Added Under:
Base Rate Loan Option		0.25	%		0.50	%		0.75	%		1.00	%
Eurodollar Rate Loan Option		1.25	%		1.50	%		1.75	%		2.00	%

Stockholders' Equity (Tables)

6 Months Ended

Jun. 30, 2015

Stockholders' Equity

Reconciliation of number of shares outstanding with the number of shares used in computing basic and diluted earnings per share

The following table reconciles the number of shares outstanding with the number of shares used in computing basic and diluted earnings per share for each of the periods presented (in thousands):

	Three Months Ended June 30,						Six Months Ended June 30,
	2015			2014			2015			2014
Common shares outstanding, end of period		37,550			37,748			37,550			37,748
Effect of using weighted average common shares outstanding		(93	)		(42	)		(180	)		(104	)

Shares used in computing earnings per share—basic		37,457			37,706			37,370			37,644
Effect of shares issuable under stock option plans based on the treasury stock method		289			144			260			165
Effect of restricted shares		171			30			131			105

Shares used in computing earnings per share—diluted		37,917			37,880			37,761			37,914

Business and Organization (Details)	6 Months Ended
Business and Organization (Details)	Jun. 30, 2015
Installation of systems in newly constructed facilities
Business and Organization
Percentage of revenue attributable to services	48.00%
Maintenance, repair and replacement services
Business and Organization
Percentage of revenue attributable to services	52.00%
HVAC
Business and Organization
Percentage of revenue attributable to services	77.00%
Plumbing
Business and Organization
Percentage of revenue attributable to services	15.00%
Building automation control systems
Business and Organization
Percentage of revenue attributable to services	5.00%
Other
Business and Organization
Percentage of revenue attributable to services	3.00%

Fair Value Measurements (Details) $ in Thousands	3 Months Ended	6 Months Ended		12 Months Ended
Fair Value Measurements (Details) $ in Thousands	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($) item	Jun. 30, 2014 USD ($)	Dec. 31, 2014 USD ($)
Fair Value Measurements
Number of employees covered under life insurance policies \| item		46
Combined face value of life insurance policies		$ 42,600
Cash surrender value		3,400
Impairment
Goodwill impairment	$ 727		$ 727	$ 727
Contingent earn-out obligations
Reconciliation of the fair value of contingent earn-out obligations that use significant unobservable inputs (Level 3)
Balance at beginning of year		670
Issuances		100
Settlements		(345)
Adjustments to fair value		(125)
Balance at end of period		300		$ 670
Recurring basis \| Total
Fair Value Measurements
Cash and cash equivalents		40,714
Life insurance - cash surrender value		3,397
Contingent earn-out obligations		300
Recurring basis \| Quoted Market Prices In Active Markets for Identical Assets (Level 1)
Fair Value Measurements
Cash and cash equivalents		40,714
Recurring basis \| Fair Value Measurements at Reporting Date Using Significant Other Observable Inputs (Level 2)
Fair Value Measurements
Life insurance - cash surrender value		3,397
Recurring basis \| Significant Unobservable Inputs (Level 3)
Fair Value Measurements
Contingent earn-out obligations		$ 300

Acquisitions (Details) $ in Thousands	3 Months Ended	6 Months Ended
Acquisitions (Details) $ in Thousands	Mar. 31, 2015 USD ($) item	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Acquisitions
Goodwill on acquisition		$ 143,569		$ 140,341	$ 114,588
Number of acquisitions \| item	2
Dyna Ten
Acquisitions
Total purchase price	$ 40,500
Goodwill on acquisition	$ 19,800
Other Acquisitions
Acquisitions
Total purchase price		$ 6,700	$ 9,500

Goodwill (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended		12 Months Ended
Goodwill (Details) - USD ($) $ in Thousands	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Changes in the carrying amount of goodwill
Balance at the beginning of period		$ 140,341	$ 114,588	$ 114,588
Additions		3,228		26,480
Impairment adjustment	$ (727)		$ (727)	(727)
Balance at the end of period		$ 143,569		$ 140,341

Long-Term Debt Obligations (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Long-Term Debt Obligations
Total debt	$ 19,683	$ 40,346
Less - current portion	(287)	(317)
Total long-term portion of debt	19,396	40,029
Revolving credit facility
Long-Term Debt Obligations
Total debt	18,000	38,500
Notes to former owners
Long-Term Debt Obligations
Total debt	1,000	1,000
Capital Lease Obligations.
Long-Term Debt Obligations
Total debt	$ 683	$ 846

Long-Term Debt Obligations (Details 2) $ in Thousands	3 Months Ended	6 Months Ended
Long-Term Debt Obligations (Details 2) $ in Thousands	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($) item	Jun. 30, 2014 USD ($)	Dec. 31, 2014 USD ($)	May 01, 2014 USD ($)
Reconciliation of Earnings before Interest Tax Depreciation and Amortization to Net Income
Goodwill impairment	$ 727		$ 727
Additional per annum interest margin added under:
Payments of debt	$ 2,000		$ 2,000
Other disclosures
Current portion of capital lease obligations		$ 287		$ 317
Revolving credit facility
Long-Term Debt Obligations
Borrowing capacity		250,000
Outstanding borrowings		18,000
Letters of credit amount outstanding		48,000
Credit available		$ 184,000
Principal financial covenants
Leverage ratio		0.23
Number of quarters of capital expenditures, tax provision, dividends and stock repurchase payments used for calculation of fixed charge coverage ratio \| item		4
Number of interest rate options \| item		2
Other disclosures
Weighted average interest rate (as a percent)		1.40%
Revolving credit facility \| Environmental Air Systems, LLC
Long-Term Debt Obligations
Borrowing capacity		$ 2,500
Credit available		$ 2,500
Other disclosures
Weighted average interest rate (as a percent)		2.00%
Revolving credit facility \| Actual
Principal financial covenants
Fixed charge coverage ratio		24.05
Revolving credit facility \| Minimum
Additional per annum interest margin added under:
Letter of credit fees (as a percent)		1.25%
Commitment fees payable on unused portion of the facility (as a percent)		0.20%
Revolving credit facility \| Minimum \| Covenant Requirement
Principal financial covenants
Net leverage ratio used as basis for other restrictions		2.00
Revolving credit facility \| Minimum \| Actual
Principal financial covenants
Fixed charge coverage ratio		2.00
Revolving credit facility \| Maximum
Principal financial covenants
Permitted amount of acquisitions per transaction		$ 25,000
Aggregate purchase price of current acquisition and acquisitions in the preceding 12 month period for determining permitted amount of acquisition per transaction		$ 60,000
Additional per annum interest margin added under:
Letter of credit fees (as a percent)		2.00%
Commitment fees payable on unused portion of the facility (as a percent)		0.35%
Revolving credit facility \| Maximum \| Through maturity
Principal financial covenants
Leverage ratio		2.75
Revolving credit facility \| Maximum \| Covenant Requirement
Principal financial covenants
Net leverage ratio used to determine exclusion of stock repurchases and the payment of dividends for calculation of the fixed charge coverage ratio		1.50
Revolving credit facility \| Maximum \| Actual
Principal financial covenants
Amount of stock repurchases to maintain maximum net leverage ratio		$ 25,000
Net leverage ratio after giving effect to stock repurchases for calculation of the fixed charge coverage ratio		1.50
Revolving credit facility \| Base rate \| Consolidated Total Indebtedness to Credit Facility Adjusted EBITDA: Less than 0.75
Market rates relating to interest options
Interest rate margin (as a percent)		0.25%
Additional per annum interest margin added under:
Additional per annum interest margin (as a percent)		0.25%
Revolving credit facility \| Base rate \| Consolidated Total Indebtedness to Credit Facility Adjusted EBITDA: 0.75 to 1.50
Market rates relating to interest options
Interest rate margin (as a percent)		0.50%
Additional per annum interest margin added under:
Additional per annum interest margin (as a percent)		0.50%
Revolving credit facility \| Base rate \| Consolidated Total Indebtedness to Credit Facility Adjusted EBITDA: 1.50 to 2.25
Market rates relating to interest options
Interest rate margin (as a percent)		0.75%
Additional per annum interest margin added under:
Additional per annum interest margin (as a percent)		0.75%
Revolving credit facility \| Base rate \| Consolidated Total Indebtedness to Credit Facility Adjusted EBITDA: 2.25 or greater
Market rates relating to interest options
Interest rate margin (as a percent)		1.00%
Additional per annum interest margin added under:
Additional per annum interest margin (as a percent)		1.00%
Revolving credit facility \| Eurodollar rate \| Consolidated Total Indebtedness to Credit Facility Adjusted EBITDA: Less than 0.75
Market rates relating to interest options
Interest rate margin (as a percent)		1.25%
Additional per annum interest margin added under:
Additional per annum interest margin (as a percent)		1.25%
Revolving credit facility \| Eurodollar rate \| Consolidated Total Indebtedness to Credit Facility Adjusted EBITDA: 0.75 to 1.50
Market rates relating to interest options
Interest rate margin (as a percent)		1.50%
Additional per annum interest margin added under:
Additional per annum interest margin (as a percent)		1.50%
Revolving credit facility \| Eurodollar rate \| Consolidated Total Indebtedness to Credit Facility Adjusted EBITDA: 1.50 to 2.25
Market rates relating to interest options
Interest rate margin (as a percent)		1.75%
Additional per annum interest margin added under:
Additional per annum interest margin (as a percent)		1.75%
Revolving credit facility \| Eurodollar rate \| Consolidated Total Indebtedness to Credit Facility Adjusted EBITDA: 2.25 or greater
Market rates relating to interest options
Interest rate margin (as a percent)		2.00%
Additional per annum interest margin added under:
Additional per annum interest margin (as a percent)		2.00%
Notes to former owners
Long-Term Debt Obligations
Outstanding balance		$ 1,000
Other disclosures
Weighted average interest rate (as a percent)		2.50%
Other debt \| Dyna Ten
Other disclosures
Capital lease obligation pertaining to acquisition in northern Texas		$ 700			$ 700
Current portion of capital lease obligations		$ 300

Commitments and Contingencies - Surety	6 Months Ended
Commitments and Contingencies - Surety	Jun. 30, 2015
Minimum
Surety
Percentage of business which has required bonds	25.00%
Maximum
Surety
Percentage of business which has required bonds	35.00%

Stockholders' Equity (Details) - shares shares in Millions	3 Months Ended		6 Months Ended
Stockholders' Equity (Details) - shares shares in Millions	Mar. 31, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Stock Options
Earnings Per Share
Anti-dilutive securities excluded from computation of earnings per share amount (in shares)	0.0	0.2	0.0	0.0

Stockholders' Equity (Details 2) - shares	3 Months Ended		6 Months Ended
Stockholders' Equity (Details 2) - shares	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Reconciliation of the number of shares outstanding with the number of shares used in computing basic and diluted earnings per share
Common shares outstanding, end of period	37,550,000	37,748,000	37,550,000	37,748,000
Effect of using weighted average common shares outstanding	(93,000)	(42,000)	(180,000)	(104,000)
Shares used in computing earnings per share - basic	37,457,000	37,706,000	37,370,000	37,644,000
Effect of shares issuable under stock option plans based on the treasury stock method	289,000	144,000	260,000	165,000
Effect of restricted shares	171,000	30,000	131,000	105,000
Shares used in computing earnings per share - diluted	37,917,000	37,880,000	37,761,000	37,914,000

Stockholders' Equity (Details 3) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	6 Months Ended	102 Months Ended
	Jun. 30, 2015	Jun. 30, 2015	Mar. 29, 2007
Share Repurchase Program
Number of shares of outstanding common stock authorized to be acquired under a stock repurchase program	7.6	7.6	1.0
Number of shares of common stock repurchased	0.1	6.6
Average price (in dollars per share)	$ 20.88	$ 11.40
Repurchased carrying basis	$ 1.5	$ 1.5