Goodwill and Other Intangible Assets - Gross Carrying Amount, Accumulated Amortization And Net Carrying Amount Of Other Intangible Assets (Details) - USD ($) $ in Millions	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014	Dec. 31, 2013
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 3,341	$ 3,471
Accumulated Amortization	(1,470)	(1,446)
Net Carrying Amount	1,871	2,025	$ 2,247	$ 2,360
Client relationships
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	2,512	2,569
Accumulated Amortization	(1,144)	(1,088)
Net Carrying Amount	1,368	1,481
Core deposits
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	671	688
Accumulated Amortization	(231)	(219)
Net Carrying Amount	440	469
Other
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	158	214
Accumulated Amortization	(95)	(139)
Net Carrying Amount	$ 63	$ 75