Loans - Purchased, Sold and Reclassified to Held-for-Sale (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Purchases	$ 285	$ 417
Sales	9,754	5,911
Retained loans reclassified to held-for-sale	349	934
Consumer, excluding credit card
Accounts, Notes, Loans and Financing Receivable [Line Items]
Purchases	119	191
Sales	47	181
Retained loans reclassified to held-for-sale	76	162
Excluded retained loans purchased from correspondents that were originated in accordance with the Firm's underwriting standards	3,200	7,000
Credit card
Accounts, Notes, Loans and Financing Receivable [Line Items]
Purchases	0	0
Sales	0	0
Retained loans reclassified to held-for-sale	0	0
Wholesale
Accounts, Notes, Loans and Financing Receivable [Line Items]
Purchases	166	226
Sales	9,707	5,730
Retained loans reclassified to held-for-sale	$ 273	$ 772