Investment Securities - Contractual Maturities and Weighted-Average Yields of Securities (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Securities available for sale
Due in 1 year or less	$ 720
Due after 1 year through 5 years	8,234
Due after 5 years through 10 years	4,764
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after 10 Years, Fair Value	63,201
Securities available for sale	76,919	$ 95,261
Amortized cost of securities available for sale
Due in 1 year or less	726
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after One Through Five Years, Amortized Cost	8,492
Due after 5 years through 10 years	5,281
Due > 10 Years	72,548
Amortized Cost	$ 87,047	94,871
Weighted average yield for securities available for sale
Due in 1 Year or Less	3.54%
Due > 1 Year through 5 Years	2.12%
Due > 5 Years through 10 Years	2.54%
Due > 10 Years	2.35%
Total weighted average yield	2.34%
U.S. Treasury securities
Securities available for sale
Due in 1 year or less	$ 0
Due after 1 year through 5 years	5,041
Due after 5 years through 10 years	0
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after 10 Years, Fair Value	0
Securities available for sale	5,041	9,442
Amortized cost of securities available for sale
Amortized Cost	5,129	9,419
RMBS, Agency
Securities available for sale
Due in 1 year or less	0
Due after 1 year through 5 years	103
Due after 5 years through 10 years	1,151
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after 10 Years, Fair Value	60,598
Securities available for sale	61,852	72,620
Amortized cost of securities available for sale
Amortized Cost	71,212	72,593
RMBS, Non-agency
Securities available for sale
Due in 1 year or less	0
Due after 1 year through 5 years	0
Due after 5 years through 10 years	0
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after 10 Years, Fair Value	737
Securities available for sale	737	996
Amortized cost of securities available for sale
Amortized Cost	653	792
RMBS
Securities available for sale
Due in 1 year or less	0
Due after 1 year through 5 years	103
Due after 5 years through 10 years	1,151
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after 10 Years, Fair Value	61,335
Securities available for sale	62,589	73,616
Amortized cost of securities available for sale
Amortized Cost	$ 71,865	73,385
Weighted average yield for securities available for sale
Weighted-average expected life	7 years 1 month 6 days
CMBS, Agency
Securities available for sale
Due in 1 year or less	$ 296
Due after 1 year through 5 years	2,125
Due after 5 years through 10 years	3,583
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after 10 Years, Fair Value	1,866
Securities available for sale	7,870	9,369
Amortized cost of securities available for sale
Amortized Cost	$ 8,626	9,237
Weighted average yield for securities available for sale
Weighted-average expected life	5 years
Other securities
Securities available for sale
Due in 1 year or less	$ 424
Due after 1 year through 5 years	965
Due after 5 years through 10 years	30
Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Rolling after 10 Years, Fair Value	0
Securities available for sale	1,419	2,834
Amortized cost of securities available for sale
Amortized Cost	$ 1,427	$ 2,830

Available-for-sale Securities, Expected Debt Maturities, Amortized Cost Basis, Rolling Maturity

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Available-for-sale Securities, Expected Debt Maturities, Fair Value, Rolling Maturity [Abstract]

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Amortized cost excluding accrued interest, before allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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