Goodwill and Other Intangible Assets and Liabilities Intangible Assets and Liabilities (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Finite-Lived Intangible Assets [Line Items]
Amortized intangible assets, gross carrying amount	$ 2,014		$ 2,013
Amortized intangible assets, accumulated amortization	1,052		899
Amortized intangible liabilities, gross carrying amount	2,056		2,056
Amortized intangible liabilities, accumulated amortization	969		842
Amortization of Intangible Assets	153	153
Amortization of Intangible Liabilities	127	141
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
Amortization of intangible assets, Remainder of 2013	153
Amortization of intangible liabilities, Remainder of 2013	125
Amortization of intangible assets, 2014	306
Amortization of intangible liabilities, 2014	179
Amortization of intangible assets, 2015	54
Amortization of intangible liabilities, 2015	115
Amortization of intangible assets, 2016	31
Amortization of intangible liabilities, 2016	101
Amortization of intangible assets, 2017	31
Amortization of intangible liabilities, 2017	$ 96