Securities - Amortized Cost and Fair Value of Securities Available for Sale (Details) - USD ($)	Jun. 30, 2025	Dec. 31, 2024
Investments, Debt and Equity Securities [Abstract]
Allowance for credit loss	$ 0	$ 0
Amortized cost and fair value of securities available for sale
Amortized Cost	2,573,662,000	968,927,000
Gross Unrealized Gains	11,235,000	694,000
Gross Unrealized Losses	(113,410,000)	(138,608,000)
Fair Value	2,471,487,000	831,013,000
Obligations of states and political subdivisions
Amortized cost and fair value of securities available for sale
Amortized Cost	268,798,000	20,266,000
Gross Unrealized Gains	2,147,000	57,000
Gross Unrealized Losses	(4,357,000)	(2,269,000)
Fair Value	266,588,000	18,054,000
Other debt securities
Amortized cost and fair value of securities available for sale
Amortized Cost	374,085,000	130,175,000
Gross Unrealized Gains	938,000	440,000
Gross Unrealized Losses	(2,547,000)	(2,655,000)
Fair Value	372,476,000	127,960,000
Government agency mortgage backed securities \| Residential mortgage backed securities:
Amortized cost and fair value of securities available for sale
Amortized Cost	674,915,000	185,292,000
Gross Unrealized Gains	2,682,000	81,000
Gross Unrealized Losses	(19,516,000)	(24,468,000)
Fair Value	658,081,000	160,905,000
Government agency mortgage backed securities \| Commercial mortgage backed securities:
Amortized cost and fair value of securities available for sale
Amortized Cost	88,320,000	11,373,000
Gross Unrealized Gains	83,000	0
Gross Unrealized Losses	(1,136,000)	(751,000)
Fair Value	87,267,000	10,622,000
Government agency collateralized mortgage obligations \| Residential mortgage backed securities:
Amortized cost and fair value of securities available for sale
Amortized Cost	760,573,000	475,311,000
Gross Unrealized Gains	3,685,000	75,000
Gross Unrealized Losses	(66,528,000)	(86,870,000)
Fair Value	697,730,000	388,516,000
Government agency collateralized mortgage obligations \| Commercial mortgage backed securities:
Amortized cost and fair value of securities available for sale
Amortized Cost	406,971,000	146,510,000
Gross Unrealized Gains	1,700,000	41,000
Gross Unrealized Losses	(19,326,000)	(21,595,000)
Fair Value	$ 389,345,000	$ 124,956,000

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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