CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Cash flows from operating activities:
Net income	$ 2,430	$ 7,487
Adjustments to reconcile net income to net cash flows provided by operating activities —
Depreciation and amortization of property and equipment	19,055	19,187
Amortization of intangible assets	398	503
Stock-based compensation expense	2,560	2,439
Deferred income taxes	(209)	(27)
Gain on sale of property and equipment	(2,026)	(612)
Other non-cash items	(289)	75
Changes in operating assets and liabilities
Accounts receivable, net	13,346	25,313
Costs and estimated earnings in excess of billings on uncompleted contracts	(22,707)	(15,619)
Receivable for insurance claims in excess of deductibles	(99)	(1,709)
Other assets	(626)	(560)
Accounts payable	15,357	5,160
Billings in excess of costs and estimated earnings on uncompleted contracts	(445)	3,462
Accrued self insurance	2,745	814
Other liabilities	(10,310)	549
Net cash flows provided by operating activities	19,180	46,462
Cash flows from investing activities:
Proceeds from sale of property and equipment	2,466	1,843
Purchases of property and equipment	(20,598)	(12,237)
Net cash flows used in investing activities	(18,132)	(10,394)
Cash flows from financing activities:
Net borrowings (repayments) under revolving lines of credit	(14,193)	20,000
Payment of principal obligations under capital leases	(516)	(144)
Proceeds from exercise of stock options	1,134	1,116
Debt issuance costs	0	(874)
Excess tax benefit from stock-based awards	0	237
Repurchase of common shares	(2,208)	(92,958)
Other financing activities	28	63
Net cash flows used in financing activities	(15,755)	(72,560)
Effect of exchange rate changes on cash	887	58
Net decrease in cash and cash equivalents	(13,820)	(36,434)
Cash and cash equivalents:
Beginning of period	23,846	39,797
End of period	10,026	3,363
Noncash investing activities:
Acquisition of property and equipment acquired under capital lease arrangements	0	4,697
Noncash financing activities:
Share repurchases not settled	0	3,037
Capital lease obligations initiated	$ 0	$ 4,697