Goodwill and Other Intangible Assets - Gross Carrying Amount, Accumulated Amortization And Net Carrying Amount Of Other Intangible Assets (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 3,300	$ 3,471
Accumulated Amortization	(1,532)	(1,446)
Net Carrying Amount	1,768	2,025	$ 2,360
Client relationships
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	2,486	2,569
Accumulated Amortization	(1,198)	(1,088)
Net Carrying Amount	1,288	1,481
Core deposits
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	667	688
Accumulated Amortization	(246)	(219)
Net Carrying Amount	421	469
Other
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	147	214
Accumulated Amortization	(88)	(139)
Net Carrying Amount	$ 59	$ 75