Income Taxes (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2013 Rate	Jun. 30, 2012 Rate	Jun. 30, 2013 Rate	Jun. 30, 2012 Rate	Dec. 31, 2012
Income Taxes [Line Items]
Indirect Tax Contingency	$ 31,000,000		$ 31,000,000
Unrecognized Tax Benefits	80,000,000		80,000,000		53,000,000
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	52,000,000		52,000,000		28,000,000
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Estimated Range of Change, Lower Bound	4,000,000		4,000,000
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Estimated Range of Change, Upper Bound	20,000,000		20,000,000
Interest released from Uncertain Tax Positions			11,000,000
Unrecognized Tax Benefits, Additional Interest Accrued			14,000,000
Unrecognized Tax Benefits, Additional Penalties Accrued			16,000,000
Income Tax Sharing Agreement With Parent - Maximum Amount	1,000,000,000		1,000,000,000
Difference Between Amounts Paid Under Tax Sharing Arrangement and for Financial Reporting Purposes	1,000,000		1,000,000
Intercompany Taxes Payable	$ 644,000,000		$ 644,000,000		$ 559,000,000
Effective Income Tax Rate, Continuing Operations	32.70%	37.10%	34.60%	37.50%