Derivatives and hedging activities - Fair Values of Derivative Instruments (Details) $ in Thousands	Mar. 31, 2025 USD ($) security	Dec. 31, 2024 USD ($)
Derivatives, Fair Value
Amount of reclassification as a reduction to interest income	$ 0
Asset derivatives fair value	18,171	$ 21,005
Liability derivatives fair value	18,400	21,065
Interest rate swaps
Derivatives, Fair Value
Asset derivatives fair value	17,744	20,537
Derivatives designated as hedging instruments \| Other Liabilities.
Derivatives, Fair Value
Liability derivatives fair value	552	447
Derivatives designated as hedging instruments \| Interest rate products \| Other Liabilities.
Derivatives, Fair Value
Notional amount	125,000
Liability derivatives fair value	552	447
Derivatives not designated as hedging instruments \| Other Assets.
Derivatives, Fair Value
Asset derivatives fair value	18,172	21,006
Derivatives not designated as hedging instruments \| Other Liabilities.
Derivatives, Fair Value
Liability derivatives fair value	17,848	20,619
Derivatives not designated as hedging instruments \| Interest rate products \| Other Assets.
Derivatives, Fair Value
Notional amount	301,563
Asset derivatives fair value	18,171	21,005
Derivatives not designated as hedging instruments \| Interest rate products \| Other Liabilities.
Derivatives, Fair Value
Notional amount	301,563
Liability derivatives fair value	17,848	20,619
Derivatives not designated as hedging instruments \| Other contracts \| Other Assets.
Derivatives, Fair Value
Notional amount	24,547
Asset derivatives fair value	1	1
Derivatives not designated as hedging instruments \| Other contracts \| Other Liabilities.
Derivatives, Fair Value
Notional amount	7,141
Derivatives not designated as hedging instruments \| Risk participation agreements
Derivatives, Fair Value
Derivative liability notional amount	7,100	7,200
Notional amount	$ 24,500	24,700
Derivatives not designated as hedging instruments \| Interest rate swaps
Derivatives, Fair Value
Number of instruments held \| security	145
Derivative liability notional amount	$ 301,600	297,900
Notional amount	301,600	$ 297,900
Asset derivatives fair value	326,100
Liability derivatives fair value	$ 308,700

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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- Definition

Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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- Definition

Nominal or face amount used to calculate payments on the derivative liability.

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Nominal or face amount used to calculate payment on derivative.

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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 estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

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