Other Assets (Schedule of Other Assets) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2020	Dec. 31, 2019
Other Assets [Abstract]
Property and equipment at cost	$ 1,485	$ 1,485	$ 1,332
Accumulated depreciation, property and equipment	(780)	(780)	(686)
Net property and equipment	705	705	646
Investments in qualified affordable housing projects	1,005	1,005	830
Nonmarketable equity investments	938	938	1,232
Accrued interest, fees, and rent receivables	840	840	589
Restricted cash held for securitization trusts	608	608	738
Equity-method investments	362	362	358
Goodwill	343	343	393
Other accounts receivable	206	206	117
Net deferred tax assets	104	104	58
Restricted cash and cash equivalents	75	75	87
Net intangible assets	55	55	69
Fair value of derivative contracts in receivable position	23	23	64
Other assets	990	990	892
Total other assets	6,254	6,254	6,073
Qualified Affordable Housing Project Investments, Commitment	455	455	372
Federal Home Loan Bank stock	394	394	701
Federal Reserve Bank stock	449	449	449
Equity securities without a readily determinable fair value	95	95	82
Equity Securities without Readily Determinable Fair Value, Upward Price Adjustment, Annual Amount	16	16
Equity securities without readily determinable fair value, impairment loss, amount	1	6
Equity securities without readily determinable fair value, upward price adjustment, cumulative amount	25	25
Impairment related to equity securities without a readily determinable fair value	12	12
Intangible Assets, Gross (Excluding Goodwill)	109	109	111
Intangible assets, accumulated amortization	$ 55	$ 55	$ 42