Interest and dividends on SAFS (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Schedule of Available-for-sale Securities [Line Items]
Interest Income, Securities, Taxable	$ 142	$ 132	$ 421	$ 397
Interest Income, Securities, Tax Exempt	2	3	8	8
Dividend Income, Operating	9	8	27	24
Interest and Dividend Income, Securities, Available-for-sale	$ 153	$ 143	$ 456	$ 429