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Federal Home Loan Bank Advances - Summary of FHLB Advances (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Federal Home Loan Bank, Advances [Line Items]
FHLB advances (fixed rates 2.25% to 5.03%    and variable rates 4.09% to 4.28%) maturing   November 2025 to January 2045	$ 5,655,200	$ 4,475,285
Fair value hedge basis adjustments and unamortized prepayment fees	8,161	(22,726)
Federal Home Loan Bank advances	$ 5,663,361	$ 4,452,559
Minimum | FHLB Advances
Federal Home Loan Bank, Advances [Line Items]
Fixed rates	2.25%
Variable rates	4.09%
Maximum | FHLB Advances
Federal Home Loan Bank, Advances [Line Items]
Fixed rates	5.03%
Variable rates	4.28%

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Advances From Federal Home Loan Banks, Fair Value Hedge Basis adjustments And Unamortized Prepayment Fees

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Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

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The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

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