Securitizations and Variable Interest Entities, Involvement with Tax Credit VIEs (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2022
Variable Interest Entity [Line Items]
Equity securities	$ 60,610	$ 64,414
Total loans	947,991	955,871	$ 911,807
Unfunded credit commitments	670,031	671,947
VIEs that we do not consolidate [Member] | Tax credit structures [Member]
Variable Interest Entity [Line Items]
Maximum exposure to loss	28,700	28,000
VIEs that we do not consolidate [Member] | Reported value measurement [Member] | Tax credit structures [Member]
Variable Interest Entity [Line Items]
Equity securities	18,600	18,700
Total loans	1,900	2,000
VIEs that we do not consolidate [Member] | Reported value measurement [Member] | Tax credit structures [Member] | Debt, guarantees, and other commitments [Member]
Variable Interest Entity [Line Items]
Unfunded credit commitments	$ 8,200	$ 7,300