Summary Of Significant Accounting Policies (Narrative) (Details) (USD $) In Millions, unless otherwise specified	0 Months Ended	12 Months Ended
	Jan. 04, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Accounting Policies [Abstract]
Reverse stock split ratio	0.14285
Percentage of stand-alone transactions selling prices falling within narrow pricing range for determining VSOE		80.00%
Pricing range (percentage) within which historical stand-alone transactions fall		15.00%
Restricted cash		$ 63	$ 63
Maximum percentage limit of debt obligation of any one issuer under Sigma Fund portfolio		5.00%
Maximum period of maturity at purchase date for floating rate investments, months		36 months
Maximum average interest rate reset of investments held by funds, days		120 days
Equity securities minimum restriction period		1 year
Summary Of Significant Accounting Policies [Line Items]
Minimum contractual term for trade receivables		1 year
Advertising expenses		$ 95	$ 98	$ 109
Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Intangible assets estimated useful lives		1 year
Maximum
Summary Of Significant Accounting Policies [Line Items]
Intangible assets estimated useful lives		10 years
Building and Building Equipment | Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Minimum useful life, years		5 years
Building and Building Equipment | Maximum
Summary Of Significant Accounting Policies [Line Items]
Minimum useful life, years		40 years
Machinery And Equipment | Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Minimum useful life, years		2 years
Machinery And Equipment | Maximum
Summary Of Significant Accounting Policies [Line Items]
Minimum useful life, years		10 years