Goodwill and Other Intangible Assets - Changes In The Carrying Amount Of Other Intangible Assets (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Finite-lived Intangible Assets [Roll Forward]
Beginning balance			$ 1,768	$ 2,025	$ 2,025
Acquisitions			217		16
Amortization	$ (55)	$ (48)	(153)	(147)	(197)
Foreign currency translation and other, net			17		(76)
Ending balance	1,849		1,849		1,768
Investment Servicing
Finite-lived Intangible Assets [Roll Forward]
Beginning balance			1,753	1,998	1,998
Acquisitions			0		16
Amortization			(141)		(187)
Foreign currency translation and other, net			17		(74)
Ending balance	1,629		1,629		1,753
Investment Management
Finite-lived Intangible Assets [Roll Forward]
Beginning balance			15	$ 27	27
Acquisitions			217		0
Amortization			(12)		(10)
Foreign currency translation and other, net			0		(2)
Ending balance	$ 220		$ 220		$ 15