Regulatory Requirements (Capital Measures) (Details) - Standardized Approach Transitional Rules - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Amount
Common Equity Tier 1 capital	$ 60,568	$ 61,134
Tier 1 capital	69,213	69,938
Total capital	79,363	80,275
Total RWA	390,390	369,578
Tier 1 leverage	69,213	69,938
Adjusted average assets	846,868	$ 842,270
SLR	69,213
Supplementary leverage exposure	$ 1,091,518
Ratio
Common Equity Tier 1 capital	15.50%	16.50%
Tier 1 capital	17.70%	18.90%
Total capital	20.30%	21.70%
Tier 1 leverage	8.20%	8.30%
SLR	6.30%
Required Ratio
Common Equity Tier 1 capital	8.60%	7.30%
Tier 1 capital	10.10%	8.80%
Total capital	12.10%	10.80%
Tier 1 leverage	4.00%	4.00%
SLR	5.00%