Fair Value of Assets and Liabilities - Summary Of The Balances Of Assets And Liabilities Measured At Fair Value On A Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Assets
Securities available for sale	$ 4,407,521	$ 6,690,778
Government-sponsored residential mortgage-backed securities
Assets
Securities available for sale	2,780,638	4,111,908
Government-sponsored commercial mortgage-backed securities
Assets
Securities available for sale	1,124,376	1,348,954
U.S. Agency bonds
Assets
Securities available for sale	216,011	952,482
U.S. Treasury securities
Assets
Securities available for sale	95,152	93,057
Other debt securities
Assets
Securities available for sale		1,285
Fair Value, Recurring
Assets
Rabbi trust investments	87,435	76,286
Loans held for sale	1,124	4,543
Risk participation agreements	151	78
Matched customer book	760	198
Foreign currency loan		2
Mortgage derivatives	69	62
Total	4,516,605	6,795,530
Liabilities
Risk participation agreements	106	130
Matched customer book	672	205
Foreign currency loan	187	93
Mortgage derivatives	36	58
Total	63,111	81,480
Fair Value, Recurring \| Designated as Hedging Instrument
Assets
Customer-related positions	10	16
Liabilities
Cash flow hedges - interest rate positions	893	2,417
Fair Value, Recurring \| Not Designated as Hedging Instrument
Assets
Customer-related positions	19,535	23,567
Liabilities
Customer-related positions	61,217	78,577
Fair Value, Recurring \| Government-sponsored residential mortgage-backed securities
Assets
Securities available for sale	2,780,638	4,111,908
Fair Value, Recurring \| Government-sponsored commercial mortgage-backed securities
Assets
Securities available for sale	1,124,376	1,348,954
Fair Value, Recurring \| U.S. Agency bonds
Assets
Securities available for sale	216,011	952,482
Fair Value, Recurring \| U.S. Treasury securities
Assets
Securities available for sale	95,152	93,057
Fair Value, Recurring \| State and municipal bonds and obligations
Assets
Securities available for sale	191,344	183,092
Fair Value, Recurring \| Other debt securities
Assets
Securities available for sale		1,285
Fair Value, Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Assets
Rabbi trust investments	81,278	69,257
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	176,430	162,314
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
Customer-related positions	0	0
Liabilities
Cash flow hedges - interest rate positions	0	0
Fair Value, Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Not Designated as Hedging Instrument
Assets
Customer-related positions	0	0
Liabilities
Customer-related positions	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	95,152	93,057
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 \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Other debt securities
Assets
Securities available for sale		0
Fair Value, Recurring \| Significant Other Observable Inputs (Level 2)
Assets
Rabbi trust investments	6,157	7,029
Loans held for sale	1,124	4,543
Risk participation agreements	151	78
Matched customer book	760	198
Foreign currency loan		2
Mortgage derivatives	69	62
Total	4,340,175	6,633,216
Liabilities
Risk participation agreements	106	130
Matched customer book	672	205
Foreign currency loan	187	93
Mortgage derivatives	36	58
Total	63,111	81,480
Fair Value, Recurring \| Significant Other Observable Inputs (Level 2) \| Designated as Hedging Instrument
Assets
Customer-related positions	10	16
Liabilities
Cash flow hedges - interest rate positions	893	2,417
Fair Value, Recurring \| Significant Other Observable Inputs (Level 2) \| Not Designated as Hedging Instrument
Assets
Customer-related positions	19,535	23,567
Liabilities
Customer-related positions	61,217	78,577
Fair Value, Recurring \| Significant Other Observable Inputs (Level 2) \| Government-sponsored residential mortgage-backed securities
Assets
Securities available for sale	2,780,638	4,111,908
Fair Value, Recurring \| Significant Other Observable Inputs (Level 2) \| Government-sponsored commercial mortgage-backed securities
Assets
Securities available for sale	1,124,376	1,348,954
Fair Value, Recurring \| Significant Other Observable Inputs (Level 2) \| U.S. Agency bonds
Assets
Securities available for sale	216,011	952,482
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	191,344	183,092
Fair Value, Recurring \| Significant Other Observable Inputs (Level 2) \| Other debt securities
Assets
Securities available for sale		1,285
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
Customer-related positions	0	0
Liabilities
Cash flow hedges - interest rate positions	0	0
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3) \| Not Designated as Hedging Instrument
Assets
Customer-related positions	0	0
Liabilities
Customer-related positions	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
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3) \| Other debt securities
Assets
Securities available for sale

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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
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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.

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No definition available.

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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 as of the balance sheet date of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as liabilities.

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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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