Allowance for Credit Losses and Reserve for Unfunded Lending Commitments - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Jan. 01, 2023	Dec. 31, 2022	Mar. 31, 2022	Dec. 31, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit loss	$ 14,318		$ 13,240
Allowance for credit losses
Accounts, Notes, Loans and Financing Receivable [Line Items]
Increase (Decrease) in Allowance for Credit Loss	1,100
Allowance for credit loss	14,318	$ 13,177	13,240	$ 11,308	$ 11,430
Credit Card | Allowance for credit losses
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit loss	10,410	9,482	9,545	8,280	8,345
Consumer Banking | Allowance for credit losses
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit loss	2,205	2,237	2,237	1,902	1,918
Commercial Banking | Allowance for credit losses
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit loss	$ 1,703	$ 1,458	$ 1,458	$ 1,126	$ 1,167