Debt (Tables)

9 Months Ended

Sep. 30, 2013

Debt Disclosure [Abstract]

Schedule of long-term debt instruments

Total debt, including the current portion of long-term debt, consisted of the following:

(millions)	September 30, 2013		December 31, 2012
6.3% senior notes due 2016	$	500	$	500
7.75% senior notes due 2018, net of discount	500		499
7.875% senior notes due 2020, net of discount	249		248
8.375% senior notes due 2018	350		350
9.75% senior notes due 2014, net of discount	59		59
10% convertible senior notes due 2018, net of discount	386		385
Ship mortgage facility (includes $4 million of current portion of long-term debt)	25		29
Credit facilities of Oman joint ventures	7		—
Industrial revenue bonds (due 2028 through 2034)	239		239
Total	$	2,315	$	2,309