Supplemental Guarantor and Non-Guarantor Financial Information (Details 4) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Supplemental guarantor and non-guarantor financial information
Net income (loss)	$ (34,492)	$ 31,936	$ (83,936)	$ 72,552
Other comprehensive income (loss), net of tax:
Change in pension and postretirement benefit plans, net of tax	4,658	3,897	9,317	7,795
Change in unrealized gain (loss) on hedges, net of tax	526	(1,987)	1,248	(3,270)
Change in foreign currency translation adjustment	(1,461)	(3,209)	(17,086)	(790)
Change in unrealized gain (loss)on investments net of tax	(1)		43	(369)
Total other comprehensive income (loss), net of tax	3,722	(1,299)	(6,478)	3,366
Total comprehensive income (loss)	(30,770)	30,637	(90,414)	75,918
Parent (Issuer)
Supplemental guarantor and non-guarantor financial information
Net income (loss)	(34,492)	31,936	(83,936)	72,552
Other comprehensive income (loss), net of tax:
Change in pension and postretirement benefit plans, net of tax	4,658	3,897	9,317	7,795
Change in unrealized gain (loss) on hedges, net of tax	526	(1,987)	1,248	(3,270)
Change in foreign currency translation adjustment	(1,461)	(3,209)	(17,086)	(790)
Change in unrealized gain (loss)on investments net of tax	(1)		43	(369)
Total other comprehensive income (loss), net of tax	3,722	(1,299)	(6,478)	3,366
Total comprehensive income (loss)	(30,770)	30,637	(90,414)	75,918
Guarantor Subsidiaries
Supplemental guarantor and non-guarantor financial information
Net income (loss)	33,122	86,314	44,184	165,447
Other comprehensive income (loss), net of tax:
Change in pension and postretirement benefit plans, net of tax				(50,756)
Change in unrealized gain (loss) on hedges, net of tax	16	29	37	49
Total other comprehensive income (loss), net of tax	16	29	37	(50,707)
Total comprehensive income (loss)	33,138	86,343	44,221	114,740
Non-Guarantor Subsidiaries
Supplemental guarantor and non-guarantor financial information
Net income (loss)	(28,416)	(27,582)	(52,004)	(41,766)
Other comprehensive income (loss), net of tax:
Change in unrealized gain (loss) on hedges, net of tax		(1,829)		(2,519)
Change in foreign currency translation adjustment	(1,461)	(3,209)	(17,086)	(790)
Change in unrealized gain (loss)on investments net of tax	(1)		43	(369)
Total other comprehensive income (loss), net of tax	(1,462)	(5,038)	(17,043)	(3,678)
Total comprehensive income (loss)	(29,878)	(32,620)	(69,047)	(45,444)
Eliminations
Supplemental guarantor and non-guarantor financial information
Net income (loss)	(4,706)	(58,732)	7,820	(123,681)
Other comprehensive income (loss), net of tax:
Change in pension and postretirement benefit plans, net of tax				50,756
Change in unrealized gain (loss) on hedges, net of tax	(16)	1,800	(37)	2,470
Change in foreign currency translation adjustment	1,461	3,209	17,086	790
Change in unrealized gain (loss)on investments net of tax	1		(43)	369
Total other comprehensive income (loss), net of tax	1,446	5,009	17,006	54,385
Total comprehensive income (loss)	$ (3,260)	$ (53,723)	$ 24,826	$ (69,296)