CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Cash flows from operating activities:
Net income	$ 18,298	$ 16,122	$ 17,235
Adjustments to reconcile net income to net cash flows provided by operating activities-
Depreciation and amortization of property and equipment	19,176	15,955	13,190
Amortization of intangible assets	335	335	335
Stock-based compensation expense	2,130	1,603	923
Excess tax benefit from stock-based awards	(1,266)	(198)	(247)
Deferred income taxes	(1,326)	1,743	3,876
Gain on sale of property and equipment	(1,174)	(750)	(418)
Other non-cash items	44	85	85
Changes in operating assets and liabilities
Accounts receivable, net	(19,739)	(6,520)	(6,604)
Costs and estimated earnings in excess of billings on uncompleted contracts	(14,395)	1,441	(4,919)
Construction materials inventory	(4,003)
Receivable for insurance claims in excess of deductibles	(1,700)	(340)	886
Other assets	3,559	662	(1,898)
Accounts payable	35,062	(1,718)	13,781
Billings in excess of costs and estimated earnings on uncompleted contracts	(20,560)	19,842	(7,035)
Accrued self insurance	4,806	944	219
Other liabilities	11,147	(4,369)	(5,498)
Net cash flows provided by operating activities	30,394	44,837	23,911
Cash flows from investing activities:
Proceeds from sale of property and equipment	1,306	1,278	748
Purchases of property and equipment	(42,342)	(21,895)	(29,680)
Net cash flows used in investing activities	(41,036)	(20,617)	(28,932)
Cash flows from financing activities:
Repayments on term loan	(30,000)
Borrowings under revolving credit facility	20,000
Repayments under revolving credit facility	(10,000)
Debt issuance costs	(569)
Payments of capital lease obligations		(42)	(44)
Equity financing costs			(33)
Employee stock option transactions	1,370	671	351
Restricted stock tax withholdings	(80)
Excess tax benefit from stock-based awards	1,266	198	247
Other financing activities	45
Net cash flows provided by (used in) financing activities	(17,968)	827	521
Net increase (decrease) in cash and cash equivalents	(28,610)	25,047	(4,500)
Cash and cash equivalents:
Beginning of period	62,623	37,576	42,076
End of period	$ 34,013	$ 62,623	$ 37,576