Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Cash flows from operating activities:
Net loss	$ (5,396)	$ (10,063)
Adjustments to reconcile net loss to net cash provided by operating activities:
Change in allowance for doubtful accounts	144	881
Change in the fair value of acquisition-related contingent consideration	(2,063)	(1,508)
Amortization and write-off of deferred financing fees	194	194
Depreciation and amortization	12,678	12,223
Stock-based compensation	2,082	1,707
Foreign exchange (gain) loss	(256)	176
Deferred income taxes	(1,042)	779
Other	752
Changes in operating assets and liabilities, net of acquisitions:
Accounts receivable	(2,852)	(2,155)
Inventories	(785)	(5,549)
Prepaid expenses and other assets	(1,549)	1,070
Accounts payable and accrued liabilities	7,439	2,076
Deferred revenue	351	(578)
Other liabilities	(679)	(435)
Net cash provided by (used in) operating activities	9,018	(1,182)
Cash flows from investing activities:
Capital expenditures	(4,515)	(5,623)
Net cash (used in) investing activities	(4,515)	(5,623)
Cash flows from financing activities:
Effect of exchange rate changes on cash and cash equivalents	(191)	200
Net increase (decrease) in cash and cash equivalents	4,312	(6,605)
Beginning of period	53,766	34,830
End of period	58,078	28,225
Noncash investing and financing activities:
Capital expenditures incurred not yet paid	467	1,314
Stock-based compensation related to capital expenditures	$ (336)	$ 159