Bank segment - Derivatives (Details) - Derivative Financial Instruments Not Designated as Hedging Instruments - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Derivative instrument
Asset derivatives	$ 175		$ 175		$ 638
Liability derivatives	88		88		11
Net gains (losses) recognized in the Statement of Income	16	$ 87	(540)	$ (3,619)
Interest rate lock commitments
Derivative instrument
Notional amount	5,635		5,635		39,377
Fair value	(85)		(85)		638
Asset derivatives	3		3		638
Liability derivatives	88		88		0
Net gains (losses) recognized in the Statement of Income	(129)	(63)	(722)	(4,228)
Forward commitments
Derivative instrument
Notional amount	5,250		5,250		38,000
Fair value	172		172		(11)
Asset derivatives	172		172		0
Liability derivatives	0		0		$ 11
Net gains (losses) recognized in the Statement of Income	$ 145	$ 150	$ 182	$ 609

Fair value, after offset of derivative liability, of 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, before offset against an obligation to return collateral under a master netting arrangement. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, after offset of derivative asset, of 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, elected not to be and before offset against a right to receive collateral under a master netting arrangement. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Fair value of the assets less the liabilities of a derivative or group of derivatives.

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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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