Fair Value Measurements (Non-Recurring) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012 Financing receivables and loans held for sale [Member]	Jun. 30, 2011 Financing receivables and loans held for sale [Member]	Jun. 30, 2012 Financing receivables and loans held for sale [Member]	Jun. 30, 2011 Financing receivables and loans held for sale [Member]	Jun. 30, 2012 Cost and equity method investments [Member]	Jun. 30, 2011 Cost and equity method investments [Member]	Jun. 30, 2012 Cost and equity method investments [Member]	Jun. 30, 2011 Cost and equity method investments [Member]	Jun. 30, 2012 Long Lived Assets, Including Real Estate [Member]	Jun. 30, 2011 Long Lived Assets, Including Real Estate [Member]	Jun. 30, 2012 Long Lived Assets, Including Real Estate [Member]	Jun. 30, 2011 Long Lived Assets, Including Real Estate [Member]	Jun. 30, 2012 Total [Member]	Jun. 30, 2011 Total [Member]	Jun. 30, 2012 Total [Member]	Jun. 30, 2011 Total [Member]	Jun. 30, 2012 Fair Value, Inputs, Level 2 [Member] Financing receivables and loans held for sale [Member]	Dec. 31, 2011 Fair Value, Inputs, Level 2 [Member] Financing receivables and loans held for sale [Member]	Jun. 30, 2012 Fair Value, Inputs, Level 2 [Member] Cost and equity method investments [Member]	Dec. 31, 2011 Fair Value, Inputs, Level 2 [Member] Cost and equity method investments [Member]	Jun. 30, 2012 Fair Value, Inputs, Level 2 [Member] Long Lived Assets, Including Real Estate [Member]	Dec. 31, 2011 Fair Value, Inputs, Level 2 [Member] Long Lived Assets, Including Real Estate [Member]	Jun. 30, 2012 Fair Value, Inputs, Level 2 [Member] Total [Member]	Dec. 31, 2011 Fair Value, Inputs, Level 2 [Member] Total [Member]	Jun. 30, 2012 Fair Value, Inputs, Level 3 [Member] Financing receivables and loans held for sale [Member]	Dec. 31, 2011 Fair Value, Inputs, Level 3 [Member] Financing receivables and loans held for sale [Member]	Jun. 30, 2012 Fair Value, Inputs, Level 3 [Member] Cost and equity method investments [Member]	Dec. 31, 2011 Fair Value, Inputs, Level 3 [Member] Cost and equity method investments [Member]	Jun. 30, 2012 Fair Value, Inputs, Level 3 [Member] Long Lived Assets, Including Real Estate [Member]	Dec. 31, 2011 Fair Value, Inputs, Level 3 [Member] Long Lived Assets, Including Real Estate [Member]	Jun. 30, 2012 Fair Value, Inputs, Level 3 [Member] Total [Member]	Dec. 31, 2011 Fair Value, Inputs, Level 3 [Member] Total [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value assets measured on non recurring basis	$ 2,110		$ 2,110																		$ 171	$ 158	$ 0	$ 0	$ 326	$ 1,343	$ 497	$ 1,501	$ 2,731	$ 5,159	$ 266	$ 403	$ 2,014	$ 3,282	$ 5,011	$ 8,844
Adjustments To Assets Measured At Fair Value On Non Recurring Basis	$ (1)	$ (8)	$ (2)	$ (13)	$ (105)	$ (263)	$ (211)	$ (570)	$ (38)	$ (127)	$ (58)	$ (176)	$ (107)	$ (343)	$ (247)	$ (863)	$ (250)	$ (733)	$ (516)	$ (1,609)