Goodwill and intangible assets - Goodwill (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Goodwill [Roll Forward]
Beginning balance	$ 17,386	$ 17,350
Foreign currency translation	(133)	(13)
Other	0
Ending balance	17,253	17,337
Investment Services
Goodwill [Roll Forward]
Beginning balance	8,332	8,333
Foreign currency translation	(24)	(6)
Other	47
Ending balance	8,355	8,327
Investment and Wealth Management
Goodwill [Roll Forward]
Beginning balance	9,007	8,970
Foreign currency translation	(109)	(7)
Other	0
Ending balance	8,898	8,963
Other
Goodwill [Roll Forward]
Beginning balance	47	47
Foreign currency translation	0	0
Other	(47)
Ending balance	$ 0	$ 47