Loans - Purchased, Sold and Reclassified to Held-for-Sale (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Accounts, Notes, Loans and Financing Receivable [Line Items]
Purchases	$ 1,472	$ 848	$ 2,090	$ 1,558
Sales	13,973	12,962	39,053	41,464
Retained loans reclassified to held-for-sale	206	461	1,224	2,178
Consumer, excluding credit card
Accounts, Notes, Loans and Financing Receivable [Line Items]
Purchases	232	180	517	536
Sales	1,957	2,474	1,957	10,440
Retained loans reclassified to held-for-sale	45	330	276	1,499
Excluded retained loans purchased from correspondents that were originated in accordance with the Firm's underwriting standards	1,400	181	2,400	465
Credit card
Accounts, Notes, Loans and Financing Receivable [Line Items]
Purchases	0	0	0	0
Sales	0	0	0	0
Retained loans reclassified to held-for-sale	0	0	0	0
Wholesale
Accounts, Notes, Loans and Financing Receivable [Line Items]
Purchases	1,240	668	1,573	1,022
Sales	12,016	10,488	37,096	31,024
Retained loans reclassified to held-for-sale	$ 161	$ 131	$ 948	$ 679