Variable Interest Entities and Securitizations - Continuing Involvement in Securitization Related VIEs (Details) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
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Qualitative and Quantitative Information, Transferor's Continuing Involvement [Line Items]
Securities held by third-party investors, non-mortgage	$ 13,766	$ 12,976
Receivables in the trust, non-mortgage	25,589	24,367
Cash balance of spread or reserve accounts, non-mortgage	0	0
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Qualitative and Quantitative Information, Transferor's Continuing Involvement [Line Items]
Securities held by third-party investors, non-mortgage	4,095	3,997
Receivables in the trust, non-mortgage	4,801	4,682
Cash balance of spread or reserve accounts, non-mortgage	$ 20	$ 23