Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Operating activities:
Net income (loss)	$ (93,368)	$ 10,073	$ 66,333
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	45,544	48,486	42,712
Goodwill impairment	79,700	0	0
Loss on asset sales and disposals	251	287	567
Change in accounts receivable	(2,698)	8,660	(6,312)
Change in inventories	(13,443)	5,979	(12,006)
Change in accounts payable	5,574	(481)	(3,466)
Accrued interest and amortization of discounts and finance fees	1,318	(1,086)	1,291
Pension & non-pension post-retirement benefits, net	1,680	(2,513)	18,865
Accrued liabilities & prepaid expenses	2,737	4,032	4,140
Income taxes	13,121	6,296	(45,003)
Share-based compensation expense	3,460	4,766	5,917
Other operating activities	1,432	(595)	(3,346)
Net cash provided by operating activities	45,308	83,904	69,692
Investing activities:
Additions to property, plant and equipment	(47,628)	(34,604)	(48,136)
Proceeds from asset sales and other	0	0	7
Net cash used in investing activities	(47,628)	(34,604)	(48,129)
Financing activities:
Borrowings on ABL credit facility	34,086	6,000	62,900
Repayments on ABL credit facility	(34,086)	(6,000)	(62,900)
Other repayments	(632)	(350)	(3,267)
Other borrowings	0	339	0
Repayments on Term Loan B	(24,400)	(24,400)	(4,400)
Stock options exercised	466	1,400	3,338
Taxes paid on distribution of equity awards	(627)	(895)	(796)
Dividends	(10,355)	(10,070)	(9,597)
Treasury shares purchased	0	(2,000)	(15,275)
Other financing activities	334	0	0
Net cash used in financing activities	(35,214)	(35,976)	(29,997)
Effect of exchange rate fluctuations on cash	1,219	(1,357)	(2,566)
Increase (decrease) in cash	(36,315)	11,967	(11,000)
Cash & cash equivalents at beginning of year	61,011	49,044	60,044
Cash & cash equivalents at end of year	24,696	61,011	49,044
Supplemental disclosure of cash flow information:
Cash paid during the year for interest, net of capitalized interest	18,638	21,553	16,545
Cash paid during the year for income taxes	$ 3,371	$ 7,559	$ 5,516