Investment Securities (Maturities of Securities Available for Sale and Held to Maturity) (Details) - USD ($) $ in Millions		Jun. 30, 2023	Dec. 31, 2022
Available for sale securities, fair value
Within 1 year		$ 17,029
After 1 year through 5 years		41,307
After 5 years through 10 years		17,703
After 10 years		49,730
Total	[1]	125,769	$ 147,871
Available for sale securities, amortized cost
Within 1 year		17,276
After 1 year through 5 years		44,216
After 5 years through 10 years		19,887
After 10 years		55,521
Amortized Cost		136,900
Portfolio layer method fair value hedge basis adjustments, excluded from amortized cost of available for sale securities		26
Held to maturity securities, fair value
Within 1 year		700
After 1 year through 5 years		6,371
After 5 years through 10 years		38,623
After 10 years		105,903
Total		151,597	158,936
Held to maturity securities, amortized cost
Within 1 year		716
After 1 year through 5 years		6,808
After 5 years through 10 years		41,871
After 10 years		116,933
Amortized Cost		166,328
U.S. agency mortgage-backed securities [Member]
Available for sale securities, fair value
Within 1 year		727
After 1 year through 5 years		14,526
After 5 years through 10 years		13,340
After 10 years		43,134
Total		71,727	77,688
Held to maturity securities, fair value
Within 1 year		700
After 1 year through 5 years		6,371
After 5 years through 10 years		38,623
After 10 years		105,903
Total		151,597	158,936
U.S. Treasury securities [Member]
Available for sale securities, fair value
Within 1 year		13,789
After 1 year through 5 years		14,707
After 5 years through 10 years		28
After 10 years		0
Total		28,524	40,002
Asset-backed securities [Member]
Available for sale securities, fair value
Within 1 year		31
After 1 year through 5 years		3,000
After 5 years through 10 years		1,745
After 10 years		6,181
Total		10,957	13,023
Corporate debt securities [Member]
Available for sale securities, fair value
Within 1 year		1,835
After 1 year through 5 years		8,259
After 5 years through 10 years		2,188
After 10 years		0
Total		12,282	12,555
Certificates of deposit [Member]
Available for sale securities, fair value
Within 1 year		348
After 1 year through 5 years		0
After 5 years through 10 years		0
After 10 years		0
Total		348	2,231
Foreign government agency securities [Member]
Available for sale securities, fair value
Within 1 year		201
After 1 year through 5 years		777
After 5 years through 10 years		0
After 10 years		0
Total		978	969
U.S. state and municipal securities [Member]
Available for sale securities, fair value
Within 1 year		0
After 1 year through 5 years		38
After 5 years through 10 years		402
After 10 years		132
Total		572	638
Non-agency commercial mortgage-backed securities [Member]
Available for sale securities, fair value
Within 1 year		0
After 1 year through 5 years		0
After 5 years through 10 years		0
After 10 years		263
Total		263	450
Other [Member]
Available for sale securities, fair value
Within 1 year		98
After 1 year through 5 years		0
After 5 years through 10 years		0
After 10 years		20
Total		$ 118	$ 315

[1] Certain prior year amounts have been reclassified to conform to the current year presentation. See Note 1 for additional information.