Investment Securities - Narrative (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Non-agency CMBS
Schedule of Held-to-maturity Securities [Line Items]
Allowance for credit loss related to held-to-maturity securities	$ 41	$ 44

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details