Derivative instruments and hedging activities (Cash flow hedges) (Detail) - Cash flow hedging - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Derivative Instruments, Gain (Loss) [Line Items]
Amount of net gain (loss) recognized in OCI on derivatives (effective portion)	$ (30)	$ 1,636
Amount of net gain (loss) reclassified from AOCI into income (effective portion)	41	1,458
Amount of net gain (loss) recognized in income on derivatives (ineffective portion)	0	0
Forward contracts
Derivative Instruments, Gain (Loss) [Line Items]
Amount of net gain (loss) recognized in OCI on derivatives (effective portion)	$ (30)	$ 1,636
Classification in the statement of operations of the net gain (loss) reclassified from AOCI into income (effective portion and ineffective portion)	Mortgage banking activities	Mortgage banking activities
Amount of net gain (loss) reclassified from AOCI into income (effective portion)	$ 41	$ 1,458
Amount of net gain (loss) recognized in income on derivatives (ineffective portion)	$ 0	$ 0

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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-Topic 815
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The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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The income statement location of the effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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No definition available.

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The net gain (loss) recognized in earnings during the reporting period representing the amount of the cash flow hedges' ineffectiveness.

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Amount, before tax and after reclassification, of gain (loss) from derivative instrument designated and qualifying cash flow hedge included in assessment of hedge effectiveness.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
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