Monetization Financing Entities (Narrative) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011		Jul. 07, 2011	Dec. 31, 2010
Notes Receivable Face Amount	$ 397
Notes, Loans and Financing Receivable, Net, Current			220	218
Notes Receivable Maturity Date	Sep. 30, 2014		Jul. 07, 2011
Monetization Loan [Member]
Loan Payable	$ 397	[1]		$ 397	[1]
Loan Maturity Date	Jan. 31, 2014

[1] The note, monetization loan and redeemable preferred securities of subsidiary are not traded in active markets. Accordingly, their fair values were calculated using a floating rate pricing model that compared the stated spread to the fair value spread to determine the price at which each of the financial instruments should trade. The model used the following inputs to calculate fair values: face value, current LIBOR rate, unobservable fair value credit spread, stated spread, maturity date and interest payment dates. The difference between the carrying amount of the note and its fair value represents an unrealized loss position for which an other-than-temporary impairment has not been recognized in earnings because we have both the intent and ability to hold the note for a period of time sufficient to allow for an anticipated recovery of fair value to the carrying amount of the note.