Investment Securities - Amortized Cost and Fair Value of Available-for-Sale Debt and Held-to-Maturity Securities (Details) - USD ($) $ in Millions		Sep. 30, 2023	Dec. 31, 2022
Available-for-Sale Debt and Other, Amortized Cost
Due in 1 year or less		$ 170
Due after 1 year through 5 years		15,597
Due after 5 years through 10 years		28,864
Due after 10 years		10,149
Other securities		777
Amortized Cost		55,557	$ 57,530
Available-for-Sale Debt and Other, Fair Value
Due in 1 year or less		166
Due after 1 year through 5 years		14,333
Due after 5 years through 10 years		24,235
Due after 10 years		8,382
Other securities		777
Fair Value	[1]	47,893	51,503
Held-to-Maturity, Amortized Cost
Due in 1 year or less		0
Due after 1 year through 5 years		0
Due after 5 years through 10 years		0
Due after 10 years		2
Other securities		0
Amortized Cost	[2]	2	5
Held-to-Maturity, Fair Value
Due in 1 year or less		0
Due after 1 year through 5 years		0
Due after 5 years through 10 years		0
Due after 10 years		2
Other securities		0
Fair Value		$ 2	$ 5

[1] Amortized cost of $55,557 and $57,530 at September 30, 2023 and December 31, 2022, respectively.

[2] Fair value of $2 and $5 at September 30, 2023 and December 31, 2022, respectively.