Intangible Assets (Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Intangible Assets [Line Items]
Goodwill	$ 4,180	$ 4,030	$ 3,814
Other intangible assets	651
Intangible assets subject to amortization	558
Intangible assets not subject to amortization	93
Amortization expense related to other intangible assets	29	9	11
Minimum [Member]
Intangible Assets [Line Items]
Amortization expense related to future intangible assets	31
Maximum [Member]
Intangible Assets [Line Items]
Amortization expense related to future intangible assets	$ 43