Fair Value Measurements (Non-Recurring) (Details) (USD $) In Millions, unless otherwise specified			3 Months Ended
	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2014 Financing receivables and loans held for sale [Member]	Mar. 31, 2013 Financing receivables and loans held for sale [Member]	Mar. 31, 2014 Cost and equity method investments [Member]	Mar. 31, 2013 Cost and equity method investments [Member]	Mar. 31, 2014 Long Lived Assets, Including Real Estate [Member]	Mar. 31, 2013 Long Lived Assets, Including Real Estate [Member]	Mar. 31, 2014 Total [Member]	Mar. 31, 2013 Total [Member]	Mar. 31, 2014 Fair Value, Inputs, Level 2 [Member] Financing receivables and loans held for sale [Member]	Dec. 31, 2013 Fair Value, Inputs, Level 2 [Member] Financing receivables and loans held for sale [Member]	Mar. 31, 2014 Fair Value, Inputs, Level 2 [Member] Cost and equity method investments [Member]	Dec. 31, 2013 Fair Value, Inputs, Level 2 [Member] Cost and equity method investments [Member]	Mar. 31, 2014 Fair Value, Inputs, Level 2 [Member] Long Lived Assets, Including Real Estate [Member]	Dec. 31, 2013 Fair Value, Inputs, Level 2 [Member] Long Lived Assets, Including Real Estate [Member]	Mar. 31, 2014 Fair Value, Inputs, Level 2 [Member] Total [Member]	Dec. 31, 2013 Fair Value, Inputs, Level 2 [Member] Total [Member]	Mar. 31, 2014 Fair Value, Inputs, Level 3 [Member] Financing receivables and loans held for sale [Member]	Dec. 31, 2013 Fair Value, Inputs, Level 3 [Member] Financing receivables and loans held for sale [Member]	Mar. 31, 2014 Fair Value, Inputs, Level 3 [Member] Cost and equity method investments [Member]	Dec. 31, 2013 Fair Value, Inputs, Level 3 [Member] Cost and equity method investments [Member]	Mar. 31, 2014 Fair Value, Inputs, Level 3 [Member] Long Lived Assets, Including Real Estate [Member]	Dec. 31, 2013 Fair Value, Inputs, Level 3 [Member] Long Lived Assets, Including Real Estate [Member]	Mar. 31, 2014 Fair Value, Inputs, Level 3 [Member] Total [Member]	Dec. 31, 2013 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	$ 730	$ 1,426									$ 87	$ 210	$ 0	$ 0	$ 326	$ 2,050	$ 413	$ 2,260	$ 1,596	$ 2,986	$ 349	$ 649	$ 192	$ 1,085	$ 2,137	$ 4,720
Adjustments To Assets Measured At Fair Value On Non Recurring Basis			$ (113)	$ (128)	$ (205)	$ (72)	$ (67)	$ (359)	$ (385)	$ (559)