Bank segment - Derivatives (Details) - Not designated as a hedging instrument - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Derivative instrument
Asset derivatives	$ 796		$ 4,536
Liability derivatives	(18)		500
Net gains (losses) recognized in the Statement of Income	(3,258)	$ 1,012
Interest rate lock commitments
Derivative instrument
Notional amount	49,316		120,980
Fair value	438		4,536
Asset derivatives	456		4,536
Liability derivatives	(18)		0
Interest rate lock commitments \| Mortgage banking income
Derivative instrument
Net gains (losses) recognized in the Statement of Income	(4,098)	1,555
Forward commitments
Derivative instrument
Notional amount	49,500		100,500
Fair value	340		(500)
Asset derivatives	340		0
Liability derivatives	0		$ 500
Forward commitments \| Mortgage banking income
Derivative instrument
Net gains (losses) recognized in the Statement of Income	$ 840	$ (543)

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 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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