UNAUDITED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Cash flows from operating activities:
Net income	$ 23,439	$ 20,438
Adjustments to reconcile net income to net cash flows provided by operating activities:
Depreciation and amortization of property and equipment	30,153	28,151
Amortization of intangible assets	2,888	979
Stock-based compensation expense	3,261	2,480
Deferred income taxes	339	342
Gain on sale of property and equipment	(2,548)	(2,869)
Other non-cash items	631	697
Changes in operating assets and liabilities, net of acquisitions:
Accounts receivable, net	(27,327)	29,232
Contract assets	(38,910)	(40,179)
Receivable for insurance claims in excess of deductibles	1,626	(3,766)
Other assets	(771)	2,928
Accounts payable	37,874	(13,781)
Contract liabilities	(397)	8,681
Accrued self insurance	(358)	3,668
Other liabilities	1,845	21,668
Net cash flows provided by operating activities	31,745	58,669
Cash flows from investing activities:
Proceeds from sale of property and equipment	2,898	3,505
Cash paid for acquired business	(79,720)	(47,082)
Purchases of property and equipment	(39,354)	(39,723)
Net cash flows used in investing activities	(116,176)	(83,300)
Cash flows from financing activities:
Net borrowings (repayments) under revolving lines of credit	67,668	(14,580)
Borrowings under equipment notes	24,037	24,934
Payment of principal obligations under equipment notes	(3,307)	0
Payment of principal obligations under finance leases	(857)	(809)
Proceeds from exercise of stock options	325	1,887
Debt refinancing costs	(1,132)	0
Repurchase of common shares	(778)	(1,043)
Other financing activities	60	9,223
Net cash flows provided by financing activities	86,016	19,612
Effect of exchange rate changes on cash	53	(24)
Net increase (decrease) in cash and cash equivalents	1,638	(5,043)
Cash and cash equivalents:
Beginning of period	7,507	5,343
End of period	$ 9,145	$ 300