Cash Pledged As Collateral Obligation To Repay

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- Definition

Derivative, Number of Instruments Terminated

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No definition available.

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Federal Home Loan Bank, Advances, Reduction of Interest Expense

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No definition available.

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- Definition

Gain (Loss) on Termination of Cash Flow Hedge

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No definition available.

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- Definition

Amount of hedged item in hedging relationship. Excludes hedged asset or liability.

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- Definition

Average period remaining until maturity of derivative contract, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument.

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Nominal or face amount used to calculate payment on derivative.

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- Definition

The number of derivative instruments of a particular group held by the entity.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period.

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Derivative Instruments - Narrative (Details)	3 Months Ended		9 Months Ended		12 Months Ended
Derivative Instruments - Narrative (Details)	Sep. 30, 2026 USD ($) contract derivativeInstrument	Sep. 30, 2025 USD ($)	Sep. 30, 2026 USD ($) contract derivativeInstrument	Sep. 30, 2025 USD ($)	Dec. 31, 2019 USD ($) derivativeInstrument	Dec. 31, 2025 USD ($) contract derivativeInstrument
Derivatives, Fair Value [Line Items]
Number of contracts \| contract	350		350			319
Derivative, notional amount	$ 3,432,026,000		$ 3,432,026,000			$ 3,291,329,000
Cash pledged as collateral, obligation to repay	$ 28,100,000		$ 28,100,000			$ 5,300,000
Derivatives designated as hedging instruments
Derivatives, Fair Value [Line Items]
Number of contracts \| contract	9		9			6
Derivative, notional amount	$ 414,178,000		$ 414,178,000			$ 114,178,000
Customer Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Number of contracts \| contract	341		341			313
Derivative, notional amount	$ 3,017,848,000		$ 3,017,848,000			$ 3,177,151,000
Interest rate swaps: \| Derivatives designated as hedging instruments
Derivatives, Fair Value [Line Items]
Number of contracts \| contract	8		8			6
Derivative, notional amount	$ 314,178,000		$ 314,178,000			$ 114,178,000
Securities pledged	800,000		800,000			$ 11,000,000.0
Interest rate swaps: \| Derivatives designated as hedging instruments \| Federal Home Loan Bank Advances
Derivatives, Fair Value [Line Items]
Number of instruments terminated \| derivativeInstrument					16
Gain on termination of cash flow hedge			100,000		$ 8,900,000
Reduction of interest expense on FHLB advances	$ 100,000	$ 200,000	$ 500,000	$ 600,000
Interest rate swaps: \| Derivatives designated as hedging instruments \| Federal Home Loan Bank Advances \| Minimum
Derivatives, Fair Value [Line Items]
Average remaining maturity					1 month
Interest rate swaps: \| Derivatives designated as hedging instruments \| Federal Home Loan Bank Advances \| Maximum
Derivatives, Fair Value [Line Items]
Average remaining maturity					7 years
Interest rate swaps: \| Derivatives designated as hedging instruments \| Junior subordinated debentures
Derivatives, Fair Value [Line Items]
Number of contracts \| derivativeInstrument	5		5			5
Derivative, notional amount	$ 64,200,000		$ 64,200,000			$ 64,200,000
Derivative, amount of hedged item	64,200,000		64,200,000			$ 64,200,000
Unrealized gain on derivatives	100,000	$ 100,000	(200,000)	$ (200,000)
Interest rate swaps: \| Derivatives designated as hedging instruments \| Loans
Derivatives, Fair Value [Line Items]
Number of contracts \| derivativeInstrument						1
Derivative, notional amount						$ 50,000,000.0
Interest rate swaps: \| Derivatives designated as hedging instruments \| Loans \| Cash Flow Hedging
Derivatives, Fair Value [Line Items]
Derivative, notional amount	$ 250,000,000.0		$ 250,000,000.0
Interest rate swaps: \| Derivatives designated as hedging instruments \| Loans \| With Maturities In Second Quarter of 2027, 2028 and 2029
Derivatives, Fair Value [Line Items]
Number of contracts \| derivativeInstrument	3		3
Derivative, notional amount	$ 250,000,000.0		$ 250,000,000.0
Interest rate swaps: \| Customer Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Number of contracts \| contract	280		280			290
Derivative, notional amount	$ 2,675,036,000		$ 2,675,036,000			$ 2,876,834,000
Interest rate swaps: \| Customer Derivatives not designated as hedging instruments \| Third party broker
Derivatives, Fair Value [Line Items]
Number of contracts \| contract	140		140			145
Derivative, notional amount	$ 1,337,518,000		$ 1,337,518,000			$ 1,438,417,000
Securities pledged	0		0			0
Variable Interest Rate \| Derivatives designated as hedging instruments \| Loans
Derivatives, Fair Value [Line Items]
Derivative, notional amount	250,000,000.0		250,000,000.0			$ 50,000,000
Variable Interest Rate \| Derivatives designated as hedging instruments \| Loans \| Cash Flow Hedging
Derivatives, Fair Value [Line Items]
Derivative, notional amount	$ 350,000,000.0		$ 350,000,000.0
Interest rate floors \| Derivatives designated as hedging instruments
Derivatives, Fair Value [Line Items]
Number of contracts \| contract	1		1			0
Derivative, notional amount	$ 100,000,000		$ 100,000,000			$ 0
Interest rate floors \| Derivatives designated as hedging instruments \| Loans
Derivatives, Fair Value [Line Items]
Number of contracts \| derivativeInstrument	1		1
Derivative, notional amount	$ 100,000,000.0		$ 100,000,000.0
Interest rate floors \| Derivatives designated as hedging instruments \| Loans \| Cash Flow Hedging
Derivatives, Fair Value [Line Items]
Derivative, notional amount	$ 100,000,000.0		$ 100,000,000.0