Bank segment - Derivatives (Details) - Not designated as a hedging instrument - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Derivative instrument
Asset derivatives	$ 1,852		$ 300
Liability derivatives	585		45
Net gains (losses) recognized in the Statement of Income	1,012	$ 253
Interest rate lock commitments
Derivative instrument
Notional amount	63,662		23,171
Fair value	1,852		297
Asset derivatives	1,852		297
Liability derivatives	0		0
Interest rate lock commitments \| Mortgage banking income
Derivative instrument
Net gains (losses) recognized in the Statement of Income	1,555	371
Forward commitments
Derivative instrument
Notional amount	50,800		29,383
Fair value	(585)		(42)
Asset derivatives	0		3
Liability derivatives	585		$ 45
Forward commitments \| Mortgage banking income
Derivative instrument
Net gains (losses) recognized in the Statement of Income	$ (543)	$ (118)

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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