Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Cash flows from operating activities:
Net income	$ 11,031	$ 25,443
Adjustments to reconcile to net cash provided by operating activities:
Depreciation and amortization	34,406	32,046
Gain on sale of fixed assets	(1,960)	(1,023)
Equity-based compensation expense	7,689	6,847
Deferred income taxes	(613)	1,799
Non-cash restructuring charges	300	2,127
Loss on sale of businesses	0	2,864
Loss on foreign currency transactions	1,351	284
Other	440	(860)
Changes in operating assets and liabilities (net of acquisitions):
Restricted cash related to operating activities	1,704	(2,215)
Receivables net, retainage and costs and estimated earnings in excess of billings	26,402	(24,738)
Inventories	(510)	3,514
Prepaid expenses and other assets	(3,094)	(17,374)
Accounts payable and accrued expenses	(41,698)	7,023
Billings in excess of costs and estimated earnings	212	31,979
Other operating	1,038	810
Net cash provided by operating activities	36,698	68,526
Cash flows from investing activities:
Capital expenditures	(31,485)	(21,337)
Proceeds from sale of fixed assets	3,083	1,706
Patent expenditures	(1,034)	(1,643)
Restricted cash related to investing activities	(1,086)	0
Purchase of Underground Solutions, Inc., net of cash acquired	(84,740)	0
Purchase of Fyfe Europe S.A. and related companies	(2,800)	0
Purchase of CIPP business of Leif M. Jensen A/S	(3,235)	0
Purchase of Concrete Solutions Limited and Building Chemical Supplies Limited	(5,532)	0
Purchase of Schultz Mechanical Contractors, Inc.	0	(6,878)
Sale of interest in Bayou Perma-Pipe Canada, Ltd., net of cash disposed	6,599	0
Payment to Fyfe Asia sellers for final net working capital	0	(1,098)
Net cash used in investing activities	(120,230)	(29,250)
Cash flows from financing activities:
Proceeds from issuance of common stock upon stock option exercises, including tax effects	37	1,299
Repurchase of common stock	(36,597)	(21,941)
Distributions to non-controlling interests	(1,276)	(472)
Payment of contingent consideration	(500)	(684)
Proceeds from notes payable	0	1,505
Principal payments on notes payable	0	(1,875)
Proceeds from line of credit	42,000	26,000
Payments on line of credit	(6,000)	0
Principal payments on long-term debt	(13,125)	(46,122)
Net cash used in financing activities	(15,461)	(42,290)
Effect of exchange rate changes on cash	561	(4,367)
Net decrease in cash and cash equivalents for the period	(98,432)	(7,381)
Cash and cash equivalents, beginning of period	209,253	174,965
Cash and cash equivalents, end of period	$ 113,264	$ 167,584