Supplemental Information About The Credit Quality Of Financing Receivables And Allowance For Losses On Financing Receivables (Non impaired general Reserve) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Financing Receivable, Recorded Investment [Line Items]
Financing receivables	$ 78,064	$ 217,382
General reserves	3,100	4,361
Total impaired loans	973	5,275
Allowance for losses (specific reserves)		553
Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
General reserves	89	758
Total impaired loans	247	3,095
Allowance for losses (specific reserves)		145
Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
General reserves	3,011	3,603
Total impaired loans	726	2,180
Allowance for losses (specific reserves)		408
Non-impaired Financing Receivables
Financing Receivable, Recorded Investment [Line Items]
Financing receivables	80,440	217,021
Non-impaired Financing Receivables | Commercial [Member]
Financing Receivable, Recorded Investment [Line Items]
Financing receivables	22,918	118,381
Non-impaired Financing Receivables | Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Financing receivables	$ 57,522	$ 98,640