Variable Interest Entities - Re-securitizations (Details) - USD ($)	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Transfers of securities to VIEs
U.S. GSEs and government agencies	$ 16,128,000,000	$ 53,923,000,000	$ 46,123,000,000
Private label securities transferred to re-securitization VIEs	0	0	$ 0
U.S. GSEs and government agencies \| Nonconsolidated re-securitization VIEs
Variable Interest Entity [Line Items]
Interest in VIEs	$ 2,580,000,000	$ 1,947,000,000

Amount of net assets (liabilities).

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