Schedule I - Condensed Financial Information of the Parent (Condensed Statements of Comprehensive Income) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Condensed Financial Statements, Captions [Line Items]
Other, net									$ 277	$ 456	$ 483
Other (income) expense									10,264	5,616	9,614
Administrative and general expenses									198,697	199,331	207,553
Loss before income taxes									(76,573)	55,720	58,028
Income tax benefit									(38,455)	11,270	15,865
Income (loss) from continuing operations, net of tax	(40,669)	7,699	(3,624)	(1,524)					(38,118)	44,450	42,163
Discontinued operations, net of tax									0	0	66,535
Net income (loss)					22,556	12,325	5,147	4,422	(38,118)	44,450	108,698
Foreign currency translation adjustment									(1,896)	(229)	145
Deferred gain on available for sale securities									442	729	265
Current period cash flow hedging activity, net of $838 tax benefit in 2014, $477 tax expense in 2013 and $2,471 tax expense in 2012									(1,518)	810	7,658
Reclassification of hedging activities into earnings, net of $489 tax benefit in 2014, $95 tax benefit in 2013 and $2,630 tax expense in 2012									898	152	(2,757)
Current period pension and postretirement plan adjustment, net of $3,292 tax benefit in 2014, $5,531 tax expense in 2013 and $1,553 tax benefit in 2012									(6,483)	8,022	(1,716)
Curtailment gain into earnings, net of $718 tax expense in 2013									0	(983)	0
Reclassification of pension and postretirement adjustments into earnings, net of $313 tax benefit in 2014, $740 tax benefit in 2013 and $2,056 tax benefit in 2012									627	1,101	5,885
Comprehensive income (loss)									(46,048)	54,052	118,178
Derivatives qualifying as hedges tax expense (benefit)									(838)	477	2,471
Reclassification adjustment from AOCI on derivatives tax expense (benefit)									(489)	(95)	2,630
Pension and other postretirement benefit plans tax expense (benefit)									(3,292)	5,531	(1,553)
Finalization of pension and non pension postretirement plan valuation tax expense									0	718	0
Amortization adjustment from AOCI pension and other post retirement plans, tax expense (benefit)									(313)	(740)	(2,056)
Parent Company
Condensed Financial Statements, Captions [Line Items]
Intercompany interest expense									1,305	1,431	1,501
Other, net									(276)	(471)	3,021
Other (income) expense									1,029	960	4,522
Administrative and general expenses									4,862	5,670	6,569
Loss before income taxes									(5,891)	(6,630)	(11,091)
Income tax benefit									(1,764)	(1,527)	(1,754)
Net loss before equity in earnings of subsidiaries									(4,127)	(5,103)	(9,337)
Equity in earnings of subsidiaries									(33,991)	49,553	51,500
Income (loss) from continuing operations, net of tax									(38,118)	44,450	42,163
Discontinued operations, net of tax									0	0	66,535
Net income (loss)									(38,118)	44,450	108,698
Foreign currency translation adjustment									(1,896)	(229)	145
Deferred gain on available for sale securities									442	729	265
Current period cash flow hedging activity, net of $838 tax benefit in 2014, $477 tax expense in 2013 and $2,471 tax expense in 2012									(1,518)	810	7,658
Reclassification of hedging activities into earnings, net of $489 tax benefit in 2014, $95 tax benefit in 2013 and $2,630 tax expense in 2012									898	152	(2,757)
Current period pension and postretirement plan adjustment, net of $3,292 tax benefit in 2014, $5,531 tax expense in 2013 and $1,553 tax benefit in 2012									(6,483)	8,022	(1,716)
Curtailment gain into earnings, net of $718 tax expense in 2013									0	(983)	0
Reclassification of pension and postretirement adjustments into earnings, net of $313 tax benefit in 2014, $740 tax benefit in 2013 and $2,056 tax benefit in 2012									627	1,101	5,885
Comprehensive income (loss)									(46,048)	54,052	118,178
Derivatives qualifying as hedges tax expense (benefit)									(838)	477	2,471
Reclassification adjustment from AOCI on derivatives tax expense (benefit)									(489)	(95)	2,630
Pension and other postretirement benefit plans tax expense (benefit)									(3,292)	5,531	(1,553)
Finalization of pension and non pension postretirement plan valuation tax expense									0	718	0
Amortization adjustment from AOCI pension and other post retirement plans, tax expense (benefit)									$ (313)	$ (740)	$ (2,056)