Other Assets (Schedule of Other Assets) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Other Assets [Abstract]
Property and equipment at cost	$ 1,541	$ 1,332
Accumulated depreciation, property and equipment	(815)	(686)
Net property and equipment	726	646
Investments in qualified affordable housing projects	1,095	830
Nonmarketable equity investments	915	1,232
Restricted cash held for securitization trusts	875	738
Accrued interest, fees, and rent receivables	704	589
Goodwill	343	393
Equity-method investments	320	358
Other accounts receivable	166	117
Operating lease right-of-use assets	162	168
Net deferred tax assets	94	58
Restricted cash and cash equivalents	78	87
Net intangible assets	50	69
Fair value of derivative contracts in receivable position	17	64
Other assets	870	724
Total other assets	6,415	6,073
Federal Home Loan Bank stock	276	701
Federal Reserve Bank stock	449	449
Equity securities without a readily determinable fair value	189	82
Equity Securities without Readily Determinable Fair Value, Upward Price Adjustment, Annual Amount	105
Equity securities without readily determinable fair value, impairment loss, amount	6
Equity securities without readily determinable fair value, upward price adjustment, cumulative amount	115
Impairment related to equity securities without a readily determinable fair value	12
Intangible Assets, Gross (Excluding Goodwill)	109	111
Intangible assets, accumulated amortization	$ 59	$ 42