Derivatives and hedging activities - Fair Values of Derivative Instruments (Details) $ in Thousands	Jun. 30, 2024 USD ($) security	Dec. 31, 2023 USD ($)
Derivatives, Fair Value
Amount of reclassification as a reduction to interest income	$ 0
Asset Derivatives	22,031	$ 19,833
Liability Derivatives	21,093	20,633
Interest rate swaps
Derivatives, Fair Value
Asset Derivatives	20,958	19,278
Derivatives designated as hedging instruments \| Other Assets.
Derivatives, Fair Value
Asset Derivatives	518
Derivatives designated as hedging instruments \| Other Liabilities.
Derivatives, Fair Value
Liability Derivatives	0	1,270
Derivatives designated as hedging instruments \| Interest rate products \| Other Assets.
Derivatives, Fair Value
Notional amount	150,000
Asset Derivatives	518
Derivatives designated as hedging instruments \| Interest rate products \| Other Liabilities.
Derivatives, Fair Value
Liability Derivatives	0	1,270
Derivatives not designated as hedging instruments \| Other Assets.
Derivatives, Fair Value
Asset Derivatives	21,515	19,836
Derivatives not designated as hedging instruments \| Other Liabilities.
Derivatives, Fair Value
Liability Derivatives	21,093	19,364
Derivatives not designated as hedging instruments \| Interest rate products \| Other Assets.
Derivatives, Fair Value
Notional amount	237,083
Asset Derivatives	21,513	19,833
Derivatives not designated as hedging instruments \| Interest rate products \| Other Liabilities.
Derivatives, Fair Value
Notional amount	237,083
Liability Derivatives	21,093	19,364
Derivatives not designated as hedging instruments \| Other \| Other Assets.
Derivatives, Fair Value
Notional amount	8,131
Asset Derivatives	2	3
Derivatives not designated as hedging instruments \| Other \| Other Liabilities.
Derivatives, Fair Value
Notional amount	$ 7,303
Derivatives not designated as hedging instruments \| Risk participation agreements
Derivatives, Fair Value
Notional amount		8,400
Derivatives not designated as hedging instruments \| Interest rate swaps
Derivatives, Fair Value
Number of instruments held \| security	119
Notional amount	$ 245,200	$ 230,300

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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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 payment on derivative.

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

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- Definition

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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