Fair Value of Assets and Liabilities - Schedule of The Balances Of Assets And Liabilities Measured At Fair Value On A Recurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Assets
Securities available for sale:	$ 4,097,842	$ 4,407,521
Government-sponsored residential mortgage-backed securities
Assets
Securities available for sale:	2,597,550	2,780,638
Government-sponsored commercial mortgage-backed securities
Assets
Securities available for sale:	1,090,894	1,124,376
U.S. Agency bonds
Assets
Securities available for sale:	130,238	216,011
U.S. Treasury securities
Assets
Securities available for sale:	95,554	95,152
Fair Value, Recurring
Assets
Rabbi trust investments	94,424	87,435
Loans held for sale	1,308	1,124
Risk participation agreements	5	151
Matched customer book	616	760
Foreign currency loan	38
Mortgage derivatives	41	69
Total	4,213,524	4,516,605
Liabilities
Risk participation agreements	2	106
Matched customer book	626	672
Foreign currency loan	14	187
Mortgage derivatives	85	36
Total	68,912	63,111
Fair Value, Recurring \| Designated as Hedging Instrument
Assets
Interest rate swap contracts:	10	10
Liabilities
Interest rate swap contracts:	241	893
Fair Value, Recurring \| Not Designated as Hedging Instrument
Assets
Interest rate swap contracts:	19,240	19,535
Liabilities
Interest rate swap contracts:	67,944	61,217
Fair Value, Recurring \| Government-sponsored residential mortgage-backed securities
Assets
Securities available for sale:	2,597,550	2,780,638
Fair Value, Recurring \| Government-sponsored commercial mortgage-backed securities
Assets
Securities available for sale:	1,090,894	1,124,376
Fair Value, Recurring \| U.S. Agency bonds
Assets
Securities available for sale:	130,238	216,011
Fair Value, Recurring \| U.S. Treasury securities
Assets
Securities available for sale:	95,554	95,152
Fair Value, Recurring \| State and municipal bonds and obligations
Assets
Securities available for sale:	183,606	191,344
Fair Value, Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Rabbi trust investments	86,874	81,278
Loans held for sale	0	0
Risk participation agreements	0	0
Matched customer book	0	0
Foreign currency loan	0
Mortgage derivatives	0	0
Total	182,428	176,430
Liabilities
Risk participation agreements	0	0
Matched customer book	0	0
Foreign currency loan	0	0
Mortgage derivatives	0	0
Total	0	0
Fair Value, Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Designated as Hedging Instrument
Assets
Interest rate swap contracts:	0	0
Liabilities
Interest rate swap contracts:	0	0
Fair Value, Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Not Designated as Hedging Instrument
Assets
Interest rate swap contracts:	0	0
Liabilities
Interest rate swap contracts:	0	0
Fair Value, Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Government-sponsored residential mortgage-backed securities
Assets
Securities available for sale:	0	0
Fair Value, Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Government-sponsored commercial mortgage-backed securities
Assets
Securities available for sale:	0	0
Fair Value, Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| U.S. Agency bonds
Assets
Securities available for sale:	0	0
Fair Value, Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| U.S. Treasury securities
Assets
Securities available for sale:	95,554	95,152
Fair Value, Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| State and municipal bonds and obligations
Assets
Securities available for sale:	0	0
Fair Value, Recurring \| Significant Other Observable Inputs (Level 2)
Assets
Rabbi trust investments	7,550	6,157
Loans held for sale	1,308	1,124
Risk participation agreements	5	151
Matched customer book	616	760
Foreign currency loan	38
Mortgage derivatives	41	69
Total	4,031,096	4,340,175
Liabilities
Risk participation agreements	2	106
Matched customer book	626	672
Foreign currency loan	14	187
Mortgage derivatives	85	36
Total	68,912	63,111
Fair Value, Recurring \| Significant Other Observable Inputs (Level 2) \| Designated as Hedging Instrument
Assets
Interest rate swap contracts:	10	10
Liabilities
Interest rate swap contracts:	241	893
Fair Value, Recurring \| Significant Other Observable Inputs (Level 2) \| Not Designated as Hedging Instrument
Assets
Interest rate swap contracts:	19,240	19,535
Liabilities
Interest rate swap contracts:	67,944	61,217
Fair Value, Recurring \| Significant Other Observable Inputs (Level 2) \| Government-sponsored residential mortgage-backed securities
Assets
Securities available for sale:	2,597,550	2,780,638
Fair Value, Recurring \| Significant Other Observable Inputs (Level 2) \| Government-sponsored commercial mortgage-backed securities
Assets
Securities available for sale:	1,090,894	1,124,376
Fair Value, Recurring \| Significant Other Observable Inputs (Level 2) \| U.S. Agency bonds
Assets
Securities available for sale:	130,238	216,011
Fair Value, Recurring \| Significant Other Observable Inputs (Level 2) \| U.S. Treasury securities
Assets
Securities available for sale:	0	0
Fair Value, Recurring \| Significant Other Observable Inputs (Level 2) \| State and municipal bonds and obligations
Assets
Securities available for sale:	183,606	191,344
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3)
Assets
Rabbi trust investments	0	0
Loans held for sale	0	0
Risk participation agreements	0	0
Matched customer book	0	0
Foreign currency loan	0
Mortgage derivatives	0	0
Total	0	0
Liabilities
Risk participation agreements	0	0
Matched customer book	0	0
Foreign currency loan	0	0
Mortgage derivatives	0	0
Total	0	0
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3) \| Designated as Hedging Instrument
Assets
Interest rate swap contracts:	0	0
Liabilities
Interest rate swap contracts:	0	0
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3) \| Not Designated as Hedging Instrument
Assets
Interest rate swap contracts:	0	0
Liabilities
Interest rate swap contracts:	0	0
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3) \| Government-sponsored residential mortgage-backed securities
Assets
Securities available for sale:	0	0
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3) \| Government-sponsored commercial mortgage-backed securities
Assets
Securities available for sale:	0	0
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3) \| U.S. Agency bonds
Assets
Securities available for sale:	0	0
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3) \| U.S. Treasury securities
Assets
Securities available for sale:	0	0
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3) \| State and municipal bonds and obligations
Assets
Securities available for sale:	$ 0	$ 0

Foreign Currency Loan, Asset

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Foreign currency loan.

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Interest rate derivative liabilities one.

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Mortgage Derivatives, Asset

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Mortgage Derivatives, Liability

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Fair value portion of asset recognized for present right to economic benefit.

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The total amount of cash and securities held by third party trustees pursuant to terms of debt instruments or other agreements as of the date of each statement of financial position presented, which can be used by the trustee only to pay the noncurrent portion of specified obligations.

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Amount excluding accrued interest, 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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Fair value as of the balance sheet date of all interest rate derivative assets designated as cash flow hedging instruments.

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Fair value as of the balance sheet date of all interest rate derivative liabilities designated as cash flow hedging instruments.

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Fair value of financial and nonfinancial obligations.

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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