Commitments, Contingencies and Guarantees - Schedule of Commitments, Contingencies and Guarantees (Details) $ in Millions	Jun. 30, 2021 USD ($)
Commitments to extend credit
Commitment, Contingencies and Guarantees disclosures
Commitments	$ 39,330
Issued standby and commercial letters of credit
Commitment, Contingencies and Guarantees disclosures
Commitments	4,255
Commitments to enter into forward-starting resale agreements
Commitment, Contingencies and Guarantees disclosures
Commitments	1,940
Other commitments
Commitment, Contingencies and Guarantees disclosures
Commitments	$ 1,304