Allowance for Credit Losses and Reserve for Unfunded Lending Commitments - Summary of Loss Sharing Arrangements (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Provision (benefit) for credit losses	$ 5,847	$ (1,944)	$ 10,264
Loss sharing agreements
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Expected reimbursement from loss sharing partners, beginning balance	1,450	2,159	2,166
Financing Receivable, Allowance for Credit Loss, Writeoff	(515)	(438)	(959)
Provision (benefit) for credit losses	623	(271)	952
Expected reimbursement from loss sharing partners, ending balance	$ 1,558	$ 1,450	$ 2,159