Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Cash flows from operating activities:
Net income (loss)	$ (40,712)	$ (90,828)	$ 102,278
Adjustments to reconcile net income to net cash provided by operations:
Impairments and other non-cash charges	12,523	75,508	0
Depreciation and amortization	37,955	43,917	42,030
Stock-based compensation expense	12,056	14,202	12,304
Provision for deferred income taxes	3,352	(503)	(2,328)
Net provision for doubtful accounts	2,416	1,886	1,252
Gain on sale of a business	0	0	(33,974)
Gain on sale of assets	(2,820)	(1,364)	(1,369)
Gain on extinguishment of debt	(1,615)	0	0
Excess tax benefit from stock-based compensation	0	(204)	(1,278)
Change in assets and liabilities:
(Increase) decrease in receivables	(1,699)	122,399	(53,494)
(Increase) decrease in inventories	16,044	21,309	(14,136)
(Increase) decrease in other assets	2,639	1,191	(546)
Increase (decrease) in accounts payable	(5,213)	(31,974)	23,606
Increase (decrease) in accounts payable	(23,831)	(34,022)	14,828
Net cash provided by operating activities	11,095	121,517	89,173
Cash flows from investing activities:
Capital expenditures	(38,440)	(69,404)	(106,973)
Decrease (increase) in restricted cash	10,060	(17,485)	0
Proceeds from sale of property, plant and equipment	4,540	2,523	3,205
Proceeds from sale of a business	0	0	89,766
Business acquisitions, net of cash acquired	(4,420)	0	0
Net cash used in investing activities	(28,260)	(84,366)	(14,002)
Cash flows from financing activities:
Borrowings on lines of credit	6,437	11,036	62,164
Payments on lines of credit	(14,269)	(12,544)	(62,445)
Proceeds from Convertible Notes due 2021	100,000	0	0
Purchases of Convertible Notes due 2017	(87,271)	0	0
Debt issuance costs	(5,403)	(2,023)	0
Other financing activities	357	(1,673)	(467)
Proceeds from employee stock plans	725	553	3,442
Purchases of treasury stock	(1,226)	(2,283)	(53,130)
Excess tax benefit from stock-based compensation	0	204	1,278
Net cash used in financing activities	(650)	(6,730)	(49,158)
Effect of exchange rate changes on cash	(1,445)	(8,335)	(6,801)
Net increase (decease) in cash and cash equivalents	(19,260)	22,086	19,212
Cash and cash equivalents at beginning of year	107,138	85,052	65,840
Cash and cash equivalents at end of year	87,878	107,138	85,052
Cash paid (received) for:
Income taxes (net of refunds)	(20,709)	10,866	56,568
Interest	$ 8,802	$ 8,464	$ 9,865