Fair Value of Assets and Liabilities - Schedule of Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	$ 712,555	$ 599,557
FHLB stock	38,801	13,838
Bank-owned life insurance	309,364	307,836
Deposits	25,105,249	25,470,751
FHLB advances	689,217	199,617
Interest rate swap collateral funds	27,991	15,321
Government-sponsored residential mortgage-backed securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	205,168	210,142
Government-sponsored commercial mortgage-backed securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	183,047	185,185
State and municipal bonds and obligations
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	282,454	167,346
Corporate bonds
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	41,886	36,884
Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Loans, net of allowance for loan losses	0	0
FHLB stock	0	0
Bank-owned life insurance	0	0
Deposits	0	0
FHLB advances	0	0
Interest rate swap collateral funds	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Government-sponsored residential mortgage-backed securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Government-sponsored commercial mortgage-backed securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| State and municipal bonds and obligations
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	0	0
Quoted Prices in Active Markets for Identical Assets (Level 1) \| Corporate bonds
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	0	0
Significant Other Observable Inputs (Level 2)
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Loans, net of allowance for loan losses	0	0
FHLB stock	38,801	13,838
Bank-owned life insurance	309,364	307,836
Deposits	25,134,586	25,469,630
FHLB advances	685,890	196,450
Interest rate swap collateral funds	27,991	15,321
Significant Other Observable Inputs (Level 2) \| Government-sponsored residential mortgage-backed securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	188,388	194,547
Significant Other Observable Inputs (Level 2) \| Government-sponsored commercial mortgage-backed securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	171,044	173,584
Significant Other Observable Inputs (Level 2) \| State and municipal bonds and obligations
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	279,331	169,861
Significant Other Observable Inputs (Level 2) \| Corporate bonds
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	43,172	37,982
Significant Unobservable Inputs (Level 3)
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Loans, net of allowance for loan losses	22,284,210	22,365,428
FHLB stock	0	0
Bank-owned life insurance	0	0
Deposits	0	0
FHLB advances	0	0
Interest rate swap collateral funds	0	0
Significant Unobservable Inputs (Level 3) \| Government-sponsored residential mortgage-backed securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	0	0
Significant Unobservable Inputs (Level 3) \| Government-sponsored commercial mortgage-backed securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	0	0
Significant Unobservable Inputs (Level 3) \| State and municipal bonds and obligations
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	0	0
Significant Unobservable Inputs (Level 3) \| Corporate bonds
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	0	0
Carrying Value
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Loans, net of allowance for loan losses	22,596,152	22,753,224
FHLB stock	38,801	13,838
Bank-owned life insurance	309,364	307,836
Deposits	25,105,249	25,470,751
FHLB advances	689,217	199,617
Interest rate swap collateral funds	27,991	15,321
Carrying Value \| Government-sponsored residential mortgage-backed securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	205,168	210,142
Carrying Value \| Government-sponsored commercial mortgage-backed securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	183,047	185,185
Carrying Value \| State and municipal bonds and obligations
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	282,454	167,346
Carrying Value \| Corporate bonds
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	41,886	36,884
Estimate of Fair Value Measurement
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Loans, net of allowance for loan losses	22,284,210	22,365,428
FHLB stock	38,801	13,838
Bank-owned life insurance	309,364	307,836
Deposits	25,134,586	25,469,630
FHLB advances	685,890	196,450
Interest rate swap collateral funds	27,991	15,321
Estimate of Fair Value Measurement \| Government-sponsored residential mortgage-backed securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	188,388	194,547
Estimate of Fair Value Measurement \| Government-sponsored commercial mortgage-backed securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	171,044	173,584
Estimate of Fair Value Measurement \| State and municipal bonds and obligations
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	279,331	169,861
Estimate of Fair Value Measurement \| Corporate bonds
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	$ 43,172	$ 37,982

Fair value assets and liabilities measured on recurring basis [Line Items].

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Interest Rate Swap Collateral Funds

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- Definition

The carrying amount of a life insurance policy on an officer, executive or employee for which the reporting entity (a bank) is entitled to proceeds from the policy upon death of the insured or surrender of the insurance policy.

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- Definition

Amount excluding accrued interest, after allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity).

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

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- Definition

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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Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

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Amortized cost, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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