Fair Value of Assets and Liabilities - Schedule of Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	$ 436,712	$ 449,721
FHLB stock	5,879	5,904
Bank-owned life insurance	166,710	164,702
Deposits	17,537,809	17,596,217
FHLB advances	17,415	17,738
Escrow deposits of borrowers	20,155	21,978
Interest rate swap collateral funds	11,370	8,500
Government-sponsored residential mortgage-backed securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	243,919	254,752
Government-sponsored commercial mortgage-backed securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	192,793	194,969
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
Escrow deposits of borrowers	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
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	5,879	5,904
Bank-owned life insurance	166,710	164,702
Deposits	17,530,331	17,593,214
FHLB advances	15,085	15,366
Escrow deposits of borrowers	20,155	21,978
Interest rate swap collateral funds	11,370	8,500
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:	214,481	230,319
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:	170,917	174,503
Significant Unobservable Inputs (Level 3)
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Loans, net of allowance for loan losses	13,245,517	13,145,455
FHLB stock	0	0
Bank-owned life insurance	0	0
Deposits	0	0
FHLB advances	0	0
Escrow deposits of borrowers	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
Carrying Value
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Loans, net of allowance for loan losses	13,953,773	13,799,367
FHLB stock	5,879	5,904
Bank-owned life insurance	166,710	164,702
Deposits	17,537,809	17,596,217
FHLB advances	17,415	17,738
Escrow deposits of borrowers	20,155	21,978
Interest rate swap collateral funds	11,370	8,500
Carrying Value \| Government-sponsored residential mortgage-backed securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	243,919	254,752
Carrying Value \| Government-sponsored commercial mortgage-backed securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	192,793	194,969
Estimate of Fair Value Measurement
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Loans, net of allowance for loan losses	13,245,517	13,145,455
FHLB stock	5,879	5,904
Bank-owned life insurance	166,710	164,702
Deposits	17,530,331	17,593,214
FHLB advances	15,085	15,366
Escrow deposits of borrowers	20,155	21,978
Interest rate swap collateral funds	11,370	8,500
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:	214,481	230,319
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:	$ 170,917	$ 174,503

Escrow deposits of borrowers.

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

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Interest Rate Swap Collateral Funds

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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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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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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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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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