Trading Securities - Schedule of Major Security Types of Trading Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2026	Dec. 31, 2025
Debt and Equity Securities, FV-NI [Line Items]
Total trading securities	$ 9,459,131	$ 7,387,187
U.S. Treasury notes
Debt and Equity Securities, FV-NI [Line Items]
Total trading securities	8,472,397	7,387,187
U.S. Treasury bills
Debt and Equity Securities, FV-NI [Line Items]
Total trading securities	$ 986,734	$ 0

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.

- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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+ Details