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	Mar. 31, 2024	Dec. 31, 2023
Assets
Securities available for sale	$ 4,287,585	$ 4,407,521
Government-sponsored residential mortgage-backed securities
Assets
Securities available for sale	2,683,627	2,780,638
Government-sponsored commercial mortgage-backed securities
Assets
Securities available for sale	1,106,783	1,124,376
U.S. Agency bonds
Assets
Securities available for sale	215,238	216,011
U.S. Treasury securities
Assets
Securities available for sale	95,085	95,152
Fair Value, Recurring
Assets
Rabbi trust investments	91,772	87,435
Loans held for sale	2,204	1,124
Risk participation agreements	6	151
Matched customer book	1,340	760
Foreign currency loan	35
Mortgage derivatives	21	69
Total	4,403,898	4,516,605
Liabilities
Risk participation agreements	3	106
Matched customer book	1,202	672
Foreign currency loan		187
Mortgage derivatives	36	36
Total	74,017	63,111
Fair Value, Recurring \| Designated as Hedging Instrument
Assets
Interest rate swap contracts	11	10
Liabilities
Interest rate swap contracts	1,595	893
Fair Value, Recurring \| Not Designated as Hedging Instrument
Assets
Interest rate swap contracts	20,924	19,535
Liabilities
Interest rate swap contracts	71,181	61,217
Fair Value, Recurring \| Government-sponsored residential mortgage-backed securities
Assets
Securities available for sale	2,683,627	2,780,638
Fair Value, Recurring \| Government-sponsored commercial mortgage-backed securities
Assets
Securities available for sale	1,106,783	1,124,376
Fair Value, Recurring \| U.S. Agency bonds
Assets
Securities available for sale	215,238	216,011
Fair Value, Recurring \| U.S. Treasury securities
Assets
Securities available for sale	95,085	95,152
Fair Value, Recurring \| State and municipal bonds and obligations
Assets
Securities available for sale	186,852	191,344
Fair Value, Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Rabbi trust investments	83,697	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	178,782	176,430
Liabilities
Risk participation agreements	0	0
Matched customer book	0	0
Foreign currency loan		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	95,085	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	8,075	6,157
Loans held for sale	2,204	1,124
Risk participation agreements	6	151
Matched customer book	1,340	760
Foreign currency loan	35
Mortgage derivatives	21	69
Total	4,225,116	4,340,175
Liabilities
Risk participation agreements	3	106
Matched customer book	1,202	672
Foreign currency loan		187
Mortgage derivatives	36	36
Total	74,017	63,111
Fair Value, Recurring \| Significant Other Observable Inputs (Level 2) \| Designated as Hedging Instrument
Assets
Interest rate swap contracts	11	10
Liabilities
Interest rate swap contracts	1,595	893
Fair Value, Recurring \| Significant Other Observable Inputs (Level 2) \| Not Designated as Hedging Instrument
Assets
Interest rate swap contracts	20,924	19,535
Liabilities
Interest rate swap contracts	71,181	61,217
Fair Value, Recurring \| Significant Other Observable Inputs (Level 2) \| Government-sponsored residential mortgage-backed securities
Assets
Securities available for sale	2,683,627	2,780,638
Fair Value, Recurring \| Significant Other Observable Inputs (Level 2) \| Government-sponsored commercial mortgage-backed securities
Assets
Securities available for sale	1,106,783	1,124,376
Fair Value, Recurring \| Significant Other Observable Inputs (Level 2) \| U.S. Agency bonds
Assets
Securities available for sale	215,238	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	186,852	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
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

No definition available.

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- Definition

Foreign currency loan.

+ References

No definition available.

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- Definition

Interest rate derivative liabilities one.

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No definition available.

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- Definition

Mortgage Derivatives, Asset

+ References

No definition available.

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Mortgage Derivatives, Liability

+ References

No definition available.

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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(b))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

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- Definition

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).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479130/326-30-45-1

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- References

No definition available.

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- Definition

Fair value portion of asset contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward contracts, and swaps.

+ References

No definition available.

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- Definition

Fair value portion of liability contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward (delivery or nondelivery) contracts, and swaps entered into.

+ References

No definition available.

+ Details

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480434/815-10-50-4B

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- Definition

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 as of the balance sheet date of all derivative assets designated as interest rate fair value hedging instruments.

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- Definition

Fair value of financial and nonfinancial obligations.

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- Definition

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

+ References

No definition available.

+ Details

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