CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 47,733	$ 48,029
Adjustments to reconcile net income to net cash provided by operating activities
Amortization of identifiable intangible assets	12,622	6,227
Depreciation expense	14,714	13,444
Goodwill impairment	1,105
Bad debt expense (benefit)	29	(177)
Deferred tax expense (benefit)	(112)	(606)
Amortization of debt financing costs	282	273
Gain on sale of assets	(464)	(523)
Changes in the fair value of contingent earn-out obligations	(1,845)	(468)
Stock-based compensation	4,317	3,868
(Increase) decrease in-
Receivables, net	(38,051)	(4,301)
Inventories	(1,059)	(298)
Prepaid expenses and other current assets	(608)	(3,648)
Costs and estimated earnings in excess of billings	(7,348)	(3,726)
Other noncurrent assets	913	(128)
Increase (decrease) in-
Accounts payable and accrued liabilities	22,595	1,628
Billings in excess of costs and estimated earnings	10,309	(10,928)
Other long-term liabilities	560	1,088
Net cash provided by operating activities	65,692	49,754
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of property and equipment	(16,830)	(17,257)
Proceeds from sales of property and equipment	784	847
Cash paid for acquisitions, net of cash acquired	(94,860)	(58,510)
Net cash used in investing activities	(110,906)	(74,920)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from revolving line of credit	140,000	144,000
Payments on revolving line of credit	(74,000)	(129,000)
Payments on other debt	(798)	(567)
Payments on capital lease obligations	(133)	(194)
Debt financing costs		(789)
Payments of dividends to stockholders	(8,199)	(7,663)
Share repurchase	(8,909)	(10,977)
Shares received in lieu of tax withholding	(1,419)	(1,304)
Proceeds from exercise of options	1,296	733
Deferred acquisition payments	(2,802)
Payments for contingent consideration arrangements	(2,400)	(200)
Net cash provided by (used in) financing activities	42,636	(5,961)
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	(2,578)	(31,127)
CASH AND CASH EQUIVALENTS, beginning of period	32,074	56,464
CASH AND CASH EQUIVALENTS, end of period	$ 29,496	$ 25,337