Commitments, Contingent Liabilities and Guarantees - Summary of Significant Commitments (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Commitments to extend credit
Long-term Purchase Commitment
Commitments	$ 80,641	$ 74,499
Letters of credit
Long-term Purchase Commitment
Commitments	1,953	1,982
Forward contracts related to residential mortgage loans held for sale
Long-term Purchase Commitment
Commitments	1,952	2,903
Purchase obligations
Long-term Purchase Commitment
Commitments	160	195
Capital commitments for private equity investments
Long-term Purchase Commitment
Commitments	124	83
Capital expenditures
Long-term Purchase Commitment
Commitments	$ 78	$ 75