Supplemental Guarantor and Non-Guarantor Financial Information (Details 3) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Revenues:
Sales	$ 1,836,343,000	$ 2,381,760,000	$ 2,562,325,000
Miscellaneous income (loss)	24,288,000	18,135,000	9,033,000
Total revenues	1,860,631,000	2,399,895,000	2,571,358,000
Cost and expenses:
Cost of sales (exclusive of depreciation and depletion)	1,558,305,000	1,796,991,000	1,561,112,000
Depreciation and depletion	311,514,000	316,232,000	230,681,000
Selling, general and administrative	99,994,000	133,467,000	165,749,000
Other postretirement benefits	58,900,000	52,852,000	40,385,000
Restructuring and asset impairment	2,883,000	49,070,000
Goodwill impairment		1,064,409,000
Total costs and expenses	2,031,596,000	3,413,021,000	1,997,927,000
Operating income (loss)	(170,965,000)	(1,013,126,000)	573,431,000
Interest expense	(233,854,000)	(139,356,000)	(96,820,000)
Interest income	1,103,000	804,000	606,000
Other income (loss)	2,875,000	(13,081,000)	17,606,000
Income (loss) from continuing operations before income tax expense (benefit)	(400,841,000)	(1,164,759,000)	494,823,000
Income tax expense (benefit)	(41,838,000)	(99,204,000)	131,225,000
Income (loss) from continuing operations	(359,003,000)	(1,065,555,000)	363,598,000
Income from discontinued operations		5,180,000
Net income (loss)	(359,003,000)	(1,060,375,000)	363,598,000
Parent (Issuer)
Revenues:
Miscellaneous income (loss)	88,000	2,233,000	21,486,000
Total revenues	88,000	2,233,000	21,486,000
Cost and expenses:
Depreciation and depletion	2,150,000	1,379,000	776,000
Selling, general and administrative	4,393,000	11,716,000	39,165,000
Other postretirement benefits	(218,000)	(449,000)	(1,360,000)
Total costs and expenses	6,325,000	12,646,000	38,581,000
Operating income (loss)	(6,237,000)	(10,413,000)	(17,095,000)
Interest expense	(269,586,000)	(162,938,000)	(131,545,000)
Interest income	6,274,000	5,895,000	1,251,000
Other income (loss)	3,993,000
Income (loss) from continuing operations before income tax expense (benefit)	(265,556,000)	(167,456,000)	(147,389,000)
Income tax expense (benefit)	(51,821,000)	(68,615,000)	(71,566,000)
Income (loss) from continuing operations	(213,735,000)	(98,841,000)	(75,823,000)
Equity in losses of subsidiaries	(145,268,000)	(961,534,000)	439,421,000
Net income (loss)	(359,003,000)	(1,060,375,000)	363,598,000
Guarantor Subsidiaries
Revenues:
Sales	1,231,883,000	1,592,680,000	1,694,235,000
Miscellaneous income (loss)	10,798,000	20,518,000	8,973,000
Total revenues	1,242,681,000	1,613,198,000	1,703,208,000
Cost and expenses:
Cost of sales (exclusive of depreciation and depletion)	911,023,000	1,039,547,000	927,465,000
Depreciation and depletion	149,096,000	141,463,000	120,086,000
Selling, general and administrative	50,073,000	71,208,000	79,564,000
Other postretirement benefits	59,118,000	53,301,000	41,745,000
Restructuring and asset impairment	(7,763,000)
Goodwill impairment		1,713,000
Total costs and expenses	1,161,547,000	1,307,232,000	1,168,860,000
Operating income (loss)	81,134,000	305,966,000	534,348,000
Interest expense		(1,826,000)	(1,629,000)
Interest income	30,983,000	28,617,000	36,554,000
Income (loss) from continuing operations before income tax expense (benefit)	112,117,000	332,757,000	569,273,000
Income tax expense (benefit)	109,318,000	85,935,000	199,886,000
Income (loss) from continuing operations	2,799,000	246,822,000	369,387,000
Income from discontinued operations		5,180,000
Net income (loss)	2,799,000	252,002,000	369,387,000
Non-Guarantor Subsidiaries
Revenues:
Sales	604,460,000	789,080,000	868,090,000
Miscellaneous income (loss)	13,402,000	(4,616,000)	(21,426,000)
Total revenues	617,862,000	784,464,000	846,664,000
Cost and expenses:
Cost of sales (exclusive of depreciation and depletion)	647,282,000	757,444,000	633,647,000
Depreciation and depletion	160,268,000	173,390,000	109,819,000
Selling, general and administrative	45,528,000	50,543,000	47,020,000
Restructuring and asset impairment	10,646,000	49,070,000
Goodwill impairment		1,062,696,000
Total costs and expenses	863,724,000	2,093,143,000	790,486,000
Operating income (loss)	(245,862,000)	(1,308,679,000)	56,178,000
Interest expense	(3,757,000)	(12,731,000)	(4,917,000)
Interest income	3,335,000	4,431,000	4,072,000
Other income (loss)	(1,118,000)	(13,081,000)	17,606,000
Income (loss) from continuing operations before income tax expense (benefit)	(247,402,000)	(1,330,060,000)	72,939,000
Income tax expense (benefit)	(99,335,000)	(116,524,000)	2,905,000
Income (loss) from continuing operations	(148,067,000)	(1,213,536,000)	70,034,000
Net income (loss)	(148,067,000)	(1,213,536,000)	70,034,000
Eliminations
Cost and expenses:
Interest expense	39,489,000	38,139,000	41,271,000
Interest income	(39,489,000)	(38,139,000)	(41,271,000)
Equity in losses of subsidiaries	145,268,000	961,534,000	(439,421,000)
Net income (loss)	$ 145,268,000	$ 961,534,000	$ (439,421,000)