Investment Securities - Amortized Cost and Fair Value of Available-for-Sale Debt and Held-to-Maturity Securities (Details) - USD ($) $ in Millions		Jun. 30, 2022	Dec. 31, 2021
Available-for-Sale Debt and Other, Amortized Cost
Due in 1 year or less		$ 436
Due after 1 year through 5 years		11,890
Due after 5 years through 10 years		30,490
Due after 10 years		12,518
Other securities		806
Amortized Cost		56,140	$ 36,941
Available-for-Sale Debt and Other, Fair Value
Due in 1 year or less		435
Due after 1 year through 5 years		11,538
Due after 5 years through 10 years		28,663
Due after 10 years		11,395
Other securities		806
Fair Value	[1]	52,837	38,110
Held-to-Maturity, Amortized Cost
Due in 1 year or less		0
Due after 1 year through 5 years		3
Due after 5 years through 10 years		0
Due after 10 years		2
Other securities		0
Amortized Cost		5	8
Held-to-Maturity, Fair Value
Due in 1 year or less		0
Due after 1 year through 5 years		3
Due after 5 years through 10 years		0
Due after 10 years		2
Other securities		0
Fair Value		$ 5	$ 8

[1] Amortized cost of $56,140 and $36,941 at June 30, 2022 and December 31, 2021, respectively.