Investments in Securities - Schedule of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Investments, Debt and Equity Securities [Abstract]
Net unrealized gains (losses) on AFS securities for which we have not recorded an allowance for credit losses	$ (25)	$ (13)
Other	43	48
Accumulated other comprehensive income	$ 18	$ 35

Amount, after tax, of accumulated increase (decrease) in equity from transaction and other event and circumstance from nonowner source.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant