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 loss	$ (6,148)	$ (40,712)	$ (90,828)
Adjustments to reconcile net income to net cash provided by operations:
Impairments and other non-cash charges	0	12,523	75,508
Depreciation and amortization	39,757	37,955	43,917
Stock-based compensation expense	10,843	12,056	14,202
Provision for deferred income taxes	(10,350)	3,352	(503)
Net provision for doubtful accounts	1,481	2,416	1,886
Loss on sale of a business	21,983	0	0
Gain on sale of assets	(5,478)	(2,820)	(1,364)
Gain on extinguishment of debt	0	(1,615)	0
Amortization of original issue discount and debt issuance costs	5,345	1,618	1,842
Excess tax benefit from stock-based compensation	0	0	(204)
Change in assets and liabilities:
(Increase) decrease in receivables	(73,722)	(1,699)	122,399
(Increase) decrease in inventories	(15,097)	16,044	21,309
(Increase) decrease in other assets	986	1,708	(651)
Increase (decrease) in accounts payable	14,153	(5,213)	(31,974)
Increase (decrease) in accrued liabilities and other	54,628	(24,518)	(34,022)
Net cash provided by operating activities	38,381	11,095	121,517
Cash flows from investing activities:
Capital expenditures	(31,371)	(38,440)	(69,404)
Proceeds from sale of property, plant and equipment	7,747	4,540	2,523
Business acquisitions, net of cash acquired	(44,750)	(4,420)	0
Net cash used in investing activities	(68,374)	(38,320)	(66,881)
Cash flows from financing activities:
Borrowings on lines of credit	176,267	6,437	11,036
Payments on lines of credit	(93,700)	(14,269)	(12,544)
Proceeds from 2021 Convertible Notes	0	100,000	0
Purchases of 2017 Convertible Notes	0	(87,271)	0
Payment on 2017 Convertible Notes	(83,252)	0	0
Debt issuance costs	(955)	(5,403)	(2,023)
Other financing activities	165	357	(1,673)
Proceeds from employee stock plans	2,424	725	553
Purchases of treasury stock	(3,239)	(1,226)	(2,283)
Excess tax benefit from stock-based compensation	0	0	204
Net cash used in financing activities	(2,290)	(650)	(6,730)
Effect of exchange rate changes on cash	2,444	(1,449)	(8,335)
Net increase (decrease) in cash, cash equivalents, and restricted cash	(29,839)	(29,324)	39,571
Cash, cash equivalents, and restricted cash at beginning of year	95,299	124,623	85,052
Cash, cash equivalents, and restricted cash at end of year	65,460	95,299	124,623
Cash paid (received) for:
Income taxes (net of refunds)	(20,396)	(20,709)	10,866
Interest	$ 8,718	$ 8,802	$ 8,464