Variable Interest Entities - Re-securitizations (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Transfers of securities to VIEs
U.S. GSEs and government agencies	$ 3,406	$ 6,076
U.S. GSEs and government agencies \| Nonconsolidated re-securitization VIEs
Variable Interest Entity [Line Items]
Interest in VIEs	$ 3,411		$ 2,580

Amount of net assets (liabilities).

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