Fair Value - Held to Maturity Investment Securities (Details) - USD ($) $ in Millions	Sep. 30, 2026	Dec. 31, 2025
Carrying Value
Schedule of Held-to-Maturity Securities [Line Items]
Held-to-maturity investment securities	$ 292	$ 464
Fair Value
Schedule of Held-to-Maturity Securities [Line Items]
Held-to-maturity investment securities	$ 289	$ 464

Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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+ Details

- Definition

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