Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Operating activities:
Net income	$ 10,073	$ 66,333	$ 4,963
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	48,486	42,712	40,388
Loss on asset sales and disposals	287	567	674
Change in accounts receivable	8,660	(6,312)	(1,808)
Change in inventories	5,979	(12,006)	(10,828)
Change in accounts payable	(481)	(3,466)	5,088
Accrued interest and amortization of discounts and finance fees	(1,086)	1,291	2,039
Call premium on senior notes	0	0	37,348
Write-off of finance fees on senior notes	0	0	9,086
Pension & non-pension postretirement benefits, net	(2,513)	18,865	(879)
Restructuring	0	0	(289)
Accrued liabilities & prepaid expenses	4,032	4,140	(7,222)
Income taxes	6,296	(45,003)	885
Share-based compensation expense	4,766	5,917	5,283
Excess tax benefit from share-based compensation, operating	(366)	(2,797)	0
Other operating activities	(1,490)	(4,142)	(2,857)
Net cash provided by operating activities	82,643	66,099	81,871
Investing activities:
Additions to property, plant and equipment	(34,604)	(48,136)	(54,393)
Proceeds from furnace malfunction insurance recovery	0	0	2,350
Proceeds from asset sales and other	0	7	24
Net cash used in investing activities	(34,604)	(48,129)	(52,019)
Financing activities:
Borrowings on ABL credit facility	6,000	62,900	83,000
Repayments on ABL credit facility	(6,000)	(62,900)	(83,000)
Other repayments	(350)	(3,267)	(5,863)
Other borrowings	339	0	5,214
Payments on 6.875% senior notes	0	0	(405,000)
Proceeds from Term Loan B	0	0	438,900
Repayments on Term Loan B	(24,400)	(4,400)	(2,200)
Call premium on senior notes	0	0	(37,348)
Stock options exercised	1,400	3,338	4,571
Excess tax benefit from share-based compensation, financing	366	2,797	0
Debt issuance costs and other	0	0	(6,959)
Dividends	(10,070)	(9,597)	0
Treasury shares purchased	(2,000)	(15,275)	(1,060)
Net cash used in financing activities	(34,715)	(26,404)	(9,745)
Effect of exchange rate fluctuations on cash	(1,357)	(2,566)	(2,271)
Increase (decrease) in cash	11,967	(11,000)	17,836
Cash & cash equivalents at beginning of year	49,044	60,044	42,208
Cash & cash equivalents at end of year	61,011	49,044	60,044
Supplemental disclosure of cash flow information:
Cash paid during the year for interest, net of capitalized interest	21,553	16,545	20,302
Cash paid during the year for income taxes	$ 7,559	$ 5,516	$ 7,228