Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Cash flows from operating activities
Net income (loss)	$ 18,979	$ 4,370	$ (33,063)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	13,390	17,916	17,472
Stock-based compensation expense	6,820	5,572	5,873
Deferred income taxes	3,744	4,084	6,947
Change in fair value of contingent consideration liability	677	10,417	(270)
Goodwill impairment charge	0	0	37,539
Intangible asset impairment charges	0	70
Bad debt provision	454	2,171	1,949
Secured asset reserve	0	0	2,023
Venezuela remeasurement charges	0	0	(890)
Excess tax benefit from exercise of stock awards	0	(4,030)	0
Other operating activities	210	210	210
Change in assets, net of acquisitions:
Accounts receivable and unbilled revenue	(40,959)	1,809	(10,361)
Inventories	(3,169)	1,690	(8,188)
Prepaid expenses and other assets	(8,989)	2,442	(6,138)
Change in liabilities, net of acquisitions:
Accounts payable	13,320	(48,955)	26,199
Accrued expenses and other liabilities	11,670	12,759	2,118
Net cash provided by operating activities	16,147	10,525	43,402
Cash flows from investing activities
Purchases of property and equipment	(12,483)	(13,319)	(15,034)
Net cash used in investing activities	(12,483)	(13,319)	(15,034)
Cash flows from financing activities
Net borrowing (repayments) of revolving credit facility	20,709	8,739	(5,281)
Net short-term secured borrowings (repayments)	(867)	405	(799)
Repurchases of common stock	(10,976)	0	(4,897)
Payments of contingent consideration	(15,345)	(11,374)	(8,010)
Proceeds from exercise of stock options	2,663	2,636	1,195
Excess tax benefit from exercise of stock awards	0	4,030	0
Other financing activities	(1,156)	(866)	(594)
Net cash provided by (used) in financing activities	(4,972)	3,570	(18,386)
Effect of exchange rate changes on cash and cash equivalents	947	(607)	(1,805)
Increase (decrease) in cash and cash equivalents	(362)	169	8,177
Cash and cash equivalents, beginning of period	30,924	30,755	22,578
Cash and cash equivalents, end of period	$ 30,562	$ 30,924	$ 30,755