Bank segment - Derivatives (Details) - Derivative Financial Instruments Not Designated as Hedging Instruments - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Derivative instrument
Asset derivatives	$ 208		$ 638
Liability derivatives	58		11
Net gains (losses) recognized in the Statement of Income	(477)	$ (3,258)
Interest rate lock commitments
Derivative instrument
Notional amount	12,342		39,377
Fair value	(18)		638
Asset derivatives	40		638
Liability derivatives	58		0
Interest rate lock commitments \| Mortgage banking income
Derivative instrument
Net gains (losses) recognized in the Statement of Income	(655)	(4,098)
Forward commitments
Derivative instrument
Notional amount	11,750		38,000
Fair value	168		(11)
Asset derivatives	168		0
Liability derivatives	0		$ 11
Forward commitments \| Mortgage banking income
Derivative instrument
Net gains (losses) recognized in the Statement of Income	$ 178	$ 840

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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