Fair Value of Assets and Liabilities - Schedule of Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	$ 481,963	$ 0
FHLB stock	18,714	10,904
Bank-owned life insurance	159,838	157,091
Deposits	18,733,381	19,628,311
Federal Home Loan Bank advances	384,215	14,020
Escrow deposits of borrowers	21,853	20,258
Interest rate swap collateral funds	16,650	0
Government-sponsored residential mortgage-backed securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	281,253
Government-sponsored commercial mortgage-backed securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	200,710
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
Federal Home Loan Bank advances	0	0
Escrow deposits of borrowers	0	0
Interest rate swap collateral funds	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
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
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	18,714	10,904
Bank-owned life insurance	159,838	157,091
Deposits	18,723,364	19,626,376
Federal Home Loan Bank advances	382,779	13,558
Escrow deposits of borrowers	21,853	20,258
Interest rate swap collateral funds	16,650
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:	250,281
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:	181,196
Significant Unobservable Inputs (Level 3)
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Loans, net of allowance for loan losses	12,378,276	12,282,323
FHLB stock	0	0
Bank-owned life insurance	0	0
Deposits	0	0
Federal Home Loan Bank advances	0	0
Escrow deposits of borrowers	0	0
Interest rate swap collateral funds	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
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
Carrying Value
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Loans, net of allowance for loan losses	12,752,942	12,157,281
FHLB stock	18,714	10,904
Bank-owned life insurance	159,838	157,091
Deposits	18,733,381	19,628,311
Federal Home Loan Bank advances	384,215	14,020
Escrow deposits of borrowers	21,853	20,258
Interest rate swap collateral funds	16,650
Carrying Value \| Government-sponsored residential mortgage-backed securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	281,253
Carrying Value \| Government-sponsored commercial mortgage-backed securities
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Held to maturity securities:	200,710
Estimate of Fair Value Measurement
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items]
Loans, net of allowance for loan losses	12,378,276	12,282,323
FHLB stock	18,714	10,904
Bank-owned life insurance	159,838	157,091
Deposits	18,723,364	19,626,376
Federal Home Loan Bank advances	382,779	13,558
Escrow deposits of borrowers	21,853	$ 20,258
Interest rate swap collateral funds	16,650
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:	250,281
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:	$ 181,196

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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