Debt (Details) (USD $) In Millions, unless otherwise specified																			3 Months Ended
	Apr. 12, 2012	Mar. 31, 2012	Dec. 31, 2011	Mar. 31, 2012 9.75% senior notes due 2014, net of discount [Member]	Dec. 31, 2011 9.75% senior notes due 2014, net of discount [Member]	Mar. 31, 2012 8.375% senior notes due 2018 [Member]	Dec. 31, 2011 8.375% senior notes due 2018 [Member]	Mar. 31, 2012 7.75% senior notes due 2018, net of discount [Member]	Dec. 31, 2011 7.75% senior notes due 2018, net of discount [Member]	Mar. 31, 2012 6.3% senior notes due 2016 [Member]	Dec. 31, 2011 6.3% senior notes due 2016 [Member]	Mar. 31, 2012 10% convertible senior notes due 2018, net of discount [Member]	Dec. 31, 2011 10% convertible senior notes due 2018, net of discount [Member]	Mar. 31, 2011 10% convertible senior notes due 2018, net of discount [Member]	Mar. 31, 2012 Ship mortgage facility (includes $7 million of current portion of long-term debt) [Member]	Dec. 31, 2011 Ship mortgage facility (includes $7 million of current portion of long-term debt) [Member]	Mar. 31, 2012 Industrial revenue bonds (due 2028 through 2034) [Member]	Dec. 31, 2011 Industrial revenue bonds (due 2028 through 2034) [Member]	Mar. 31, 2012 Maximum [Member] Industrial revenue bonds (due 2028 through 2034) [Member]	Mar. 31, 2012 Minimum [Member] Industrial revenue bonds (due 2028 through 2034) [Member]
Total debt, including the current portion of long-term debt
Total debt		$ 2,303	$ 2,304	$ 297	$ 297	$ 350	$ 350	$ 499	$ 499	$ 500	$ 500	$ 384	$ 383		$ 34	$ 36	$ 239	$ 239
Debt (Textual) [Abstract]
Interest rate of senior notes	7.875%			9.75%	9.75%	8.375%	8.375%	7.75%	7.75%	6.30%	6.30%	10.00%	10.00%	10.00%
Current portion of long-term debt		$ 7	$ 7												$ 7	$ 7
Average maturity of industrial revenue bonds																			2034	2028