Other Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Schedule Of Other Assets [Line Items]
Other assets	$ 371,318	$ 374,592
Federal Home Loan Bank ("FHLB") and Federal Reserve Bank ("Federal Reserve")
Schedule Of Other Assets [Line Items]
Fair value of equity securities	125,200	128,100
First National Bankers' Bank and Other Miscellaneous Holdings
Schedule Of Other Assets [Line Items]
Fair value of equity securities	99,100	97,100
Remaining Capital Commitments
Schedule Of Other Assets [Line Items]
Fair value of equity securities	$ 25,300	$ 27,000

Amount of assets classified as other.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant