Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Cash flows from operating activities:
Net income	$ 18,068	$ 649
Adjustments to reconcile net income to net cash provided by operations:
Depreciation and amortization	22,755	19,244
Stock-based compensation expense	4,848	5,874
Provision for deferred income taxes	243	(3,672)
Net provision for doubtful accounts	1,229	1,412
Gain on sale of assets	(371)	(1,266)
Amortization of original issue discount and debt issuance costs	2,643	2,679
Change in assets and liabilities:
Increase in receivables	(1,185)	(48,612)
Increase in inventories	(21,459)	(10,500)
Increase in other assets	(3,417)	(2,773)
Increase in accounts payable	6,659	15,590
Increase (decrease) in accrued liabilities and other	(9,326)	43,685
Net cash provided by operating activities	20,687	22,310
Cash flows from investing activities:
Capital expenditures	(24,458)	(16,644)
Refund of proceeds from sale of a business	(13,974)	0
Proceeds from sale of property, plant and equipment	920	1,222
Business acquisitions, net of cash acquired	(249)	0
Net cash used in investing activities	(37,761)	(15,422)
Cash flows from financing activities:
Borrowings on lines of credit	203,716	0
Payments on lines of credit	(171,796)	0
Debt issuance costs	(11)	(335)
Proceeds from employee stock plans	3,700	1,517
Purchases of treasury stock	(3,074)	(2,382)
Other financing activities	2,515	2,333
Net cash provided by financing activities	35,050	1,133
Effect of exchange rate changes on cash	(2,926)	2,017
Net increase in cash, cash equivalents, and restricted cash	15,050	10,038
Cash, cash equivalents, and restricted cash at beginning of period	65,460	95,299
Cash, cash equivalents, and restricted cash at end of period	$ 80,510	$ 105,337