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Securities - Narrative (Details)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2025 USD ($) debt_security bond	Jun. 30, 2024 USD ($)	Jun. 30, 2025 USD ($) debt_security bond	Jun. 30, 2024 USD ($)	Dec. 31, 2024 USD ($) debt_security	Dec. 31, 2023 USD ($)
Schedule of Investments [Line Items]
Transferred Securities, Unrealized Loss, Before Tax	$ 101,100,000		$ 101,100,000		$ 105,100,000
Securities transferred, Unrealized Loss, Net of Tax	79,800,000		79,800,000		83,000,000.0
Fair value of securities transferred from AFS to HTM			0		0
Available-for-sale Securities, Gross Realized Gain (Loss) [Abstract]
Net gain (loss) on sale of securities AFS	0	$ (563,000)	(554,000)	$ (581,000)
Gross realized losses on AFS securities			1,200,000	4,600,000
Gross realized gains on AFS securities			600,000	88,000
Proceeds from sale of AFS securities			120,242,000	100,259,000
Equity investments	9,502,000		9,502,000		9,467,000
Debt Securities, Held-to-maturity, Sale or Transfer of Investment [Abstract]
Sale of HTM portfolio			0	0
Interest receivable	45,546,000		45,546,000		$ 46,724,000
FHLB stock with other-than-temporary impairment	0		0
Other-than-temporarily impaired equity investments	$ 0		$ 0
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions | debt_security	335		335		421
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	$ 390,095,000	451,996,000	$ 390,095,000	451,996,000	$ 426,161,000	$ 560,510,000
Less: Net gains recognized during the period on equity investments sold during the period	0	0	0	0
Debt Securities, Available-for-Sale, Accrued Interest	12,300,000		12,300,000		13,600,000
Debt Securities, Held-to-Maturity, Accrued Interest	$ 12,800,000		$ 12,800,000		12,900,000
Held-To-Maturity Securities, Number Of Bonds Below Investment Grade | bond	2		2
Gain (Loss) on Hedging Activity			$ 1,200,000	4,000,000.0
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, Nonaccrual	$ 0		0		0
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss	1,272,961,000		1,272,961,000		1,279,234,000
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	0		0		0
State and political subdivisions
Debt Securities, Held-to-maturity, Sale or Transfer of Investment [Abstract]
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, Credit Loss Expense (Reversal)			(55,000)	$ 0
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss	1,041,998,000		1,041,998,000		1,040,912,000
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	0		0		0
Corporate bonds and other
Debt Securities, Held-to-maturity, Sale or Transfer of Investment [Abstract]
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, Credit Loss Expense (Reversal)	9,000	$ 0
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss	120,415,000		120,415,000		124,095,000
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest	0		0		0
Asset Pledged as Collateral
Debt Securities, Held-to-maturity, Sale or Transfer of Investment [Abstract]
Debt Securities	2,160,000,000		2,160,000,000		2,180,000,000
Asset Pledged As Collateral, Excess Amount
Debt Securities, Held-to-maturity, Sale or Transfer of Investment [Abstract]
Debt Securities	383,600,000		383,600,000		431,700,000
Financial Asset, Past Due
Debt Securities, Held-to-maturity, Sale or Transfer of Investment [Abstract]
Debt Securities, Held-to-Maturity, Excluding Accrued Interest, before Allowance for Credit Loss	$ 0		$ 0		$ 0

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