Bank segment - Derivatives (Details) - Not designated as a hedging instrument - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Derivative instrument
Asset derivatives	$ 2,341		$ 2,341		$ 300
Liability derivatives	287		287		45
Net gains (losses) recognized in the Statement of Income	787	$ 57	1,799	$ 310
Interest rate lock commitments
Derivative instrument
Notional amount	70,190		70,190		23,171
Fair value	2,341		2,341		297
Asset derivatives	2,341		2,341		297
Liability derivatives	0		0		0
Interest rate lock commitments \| Mortgage banking income
Derivative instrument
Net gains (losses) recognized in the Statement of Income	489	11	2,044	382
Forward commitments
Derivative instrument
Notional amount	57,750		57,750		29,383
Fair value	(287)		(287)		(42)
Asset derivatives	0		0		3
Liability derivatives	287		287		$ 45
Forward commitments \| Mortgage banking income
Derivative instrument
Net gains (losses) recognized in the Statement of Income	$ 298	$ 46	$ (245)	$ (72)

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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