Fair Value of Assets and Liabilities - Schedule of Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	$ 465,061	$ 476,647
FHLB stock	26,894	41,363
Bank-owned life insurance	162,718	160,790
Deposits	18,180,972	18,974,359
Long-term Federal Home Loan Bank advances	12,726	12,787
Escrow deposits of borrowers	22,980	22,314
Interest rate swap collateral funds	14,210	14,430
Government-sponsored residential mortgage-backed securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	266,140	276,493
Government-sponsored commercial mortgage-backed securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	198,921	200,154
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
Long-term Federal Home Loan Bank 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	26,894	41,363
Bank-owned life insurance	162,718	160,790
Deposits	18,164,826	18,960,407
Long-term Federal Home Loan Bank advances	312,662	702,954
Escrow deposits of borrowers	22,980	22,314
Interest rate swap collateral funds	14,210	14,430
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:	238,139	246,343
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:	174,725	176,883
Significant Unobservable Inputs (Level 3)
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Loans, net of allowance for loan losses	13,187,441	13,149,096
FHLB stock	0	0
Bank-owned life insurance	0	0
Deposits	0	0
Long-term Federal Home Loan Bank 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	13,798,721	13,420,317
FHLB stock	26,894	41,363
Bank-owned life insurance	162,718	160,790
Deposits	18,180,972	18,974,359
Long-term Federal Home Loan Bank advances	314,021	704,084
Escrow deposits of borrowers	22,980	22,314
Interest rate swap collateral funds	14,210	14,430
Carrying Value \| Government-sponsored residential mortgage-backed securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	266,140	276,493
Carrying Value \| Government-sponsored commercial mortgage-backed securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	198,921	200,154
Estimate of Fair Value Measurement
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Loans, net of allowance for loan losses	13,187,441	13,149,096
FHLB stock	26,894	41,363
Bank-owned life insurance	162,718	160,790
Deposits	18,164,826	18,960,407
Long-term Federal Home Loan Bank advances	312,662	702,954
Escrow deposits of borrowers	22,980	22,314
Interest rate swap collateral funds	14,210	14,430
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:	238,139	246,343
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:	$ 174,725	$ 176,883

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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