Bank segment - Derivatives (Details) - Derivative Financial Instruments Not Designated as Hedging Instruments - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Derivative instrument
Asset derivatives	$ 377		$ 377		$ 4,536
Liability derivatives	47		47		500
Net gains (losses) recognized in the Statement of Income	(448)	$ 787	(3,706)	$ 1,799
Interest rate lock commitments
Derivative instrument
Notional amount	15,516		15,516		120,980
Fair value	371		371		4,536
Asset derivatives	371		371		4,536
Liability derivatives	0		0		0
Interest rate lock commitments \| Mortgage banking income
Derivative instrument
Net gains (losses) recognized in the Statement of Income	(67)	489	(4,165)	2,044
Forward commitments
Derivative instrument
Notional amount	20,036		20,036		100,500
Fair value	(41)		(41)		(500)
Asset derivatives	6		6		0
Liability derivatives	47		47		$ 500
Forward commitments \| Mortgage banking income
Derivative instrument
Net gains (losses) recognized in the Statement of Income	$ (381)	$ 298	$ 459	$ (245)

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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