Debt (Schedule of Long-term Debt) (Details) (USD $) In Millions, unless otherwise specified			1 Months Ended	9 Months Ended	12 Months Ended	1 Months Ended	9 Months Ended	12 Months Ended	1 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended		9 Months Ended		9 Months Ended
	Sep. 30, 2012	Dec. 31, 2011	May 31, 2011 Term B Loan Facility [Member]	Sep. 30, 2012 Term C Loan Facility [Member]	Dec. 31, 2011 Term C Loan Facility [Member]	Sep. 30, 2010 Senior Unsecured Notes Due 2018 [Member]	Sep. 30, 2012 Senior Unsecured Notes Due 2018 [Member]	Dec. 31, 2011 Senior Unsecured Notes Due 2018 [Member]	May 31, 2011 Senior Unsecured Notes Due 2021 [Member]	Sep. 30, 2012 Senior Unsecured Notes Due 2021 [Member]	Dec. 31, 2011 Senior Unsecured Notes Due 2021 [Member]	Sep. 30, 2012 Pollution Control and Industrial Revenue Bonds [Member]	Dec. 31, 2011 Pollution Control and Industrial Revenue Bonds [Member]	Sep. 30, 2012 Obligations Under Capital Leases [Member]	Dec. 31, 2011 Obligations Under Capital Leases [Member]	Sep. 30, 2012 Other Bank Obligations [Member]	Dec. 31, 2011 Other Bank Obligations [Member]
Long-Term Debt
Senior credit facilities			$ 516	$ 1,375	$ 1,386
Senior unsecured notes							600	600		400	400
Year of maturity			Apr. 02, 2014	Oct. 31, 2016	Oct. 31, 2016	Oct. 15, 2018	Oct. 15, 2018	Oct. 15, 2018	Jun. 15, 2021	Jun. 15, 2021	Jun. 15, 2021
Interest rate, stated percentage						6.625%	6.625%	6.625%	5.875%	5.875%	5.875%
Other long-term debt												182	182
Interest rate, stated percentage range, minimum												5.70%				6.20%
Interest rate, stated percentage range, maximum												6.70%				6.30%
Year of maturity, range end												Nov. 01, 2030		Mar. 31, 2054		Mar. 21, 2017
Capital lease obligations														237	248
Other loans payable																87	95
Subtotal	2,881	2,911
Current installments of long-term debt	(42)	(38)
Total	$ 2,839	$ 2,873