FHLB Advances, Other Borrowings and Subordinated Notes - Schedule of FHLB Advances, Other Borrowings and Subordinated Notes (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024	Sep. 30, 2024
Debt Disclosure [Abstract]
FHLB advances	$ 3,151,309	$ 3,151,309	$ 3,171,309
Other borrowings:
Notes payable	121,368	142,763	149,894
Secured borrowings	401,863	334,934	439,513
Other	56,097	57,106	57,636
Total other borrowings	579,328	534,803	647,043
Subordinated notes	298,536	298,283	298,188
Total FHLB advances, other borrowings and subordinated notes	$ 4,029,173	$ 3,984,395	$ 4,116,540

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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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Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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The carrying amount as of the balance sheet date for the aggregate of other miscellaneous borrowings owed by the reporting entity.

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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of subordinated debt (with initial maturities beyond one year or beyond the operating cycle if longer). Subordinated debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets.

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