Intangible Assets (Details 1) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012 Y	Mar. 31, 2011
Intangible Assets - Additional Information
Amortization expense on intangible assets excluding goodwill	$ 80	$ 84
Weighted Average Amortization Period for all Intangible Assets (Years)	21
Estimated amortization charged to income, 2012	241
Estimated amortization charged to income, 2013	304
Estimated amortization charged to income, 2014	298
Estimated amortization charged to income, 2015	287
Estimated amortization charged to income, 2016	268
Estimated amortization charged to income, 2017	$ 260