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Amount, after tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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Derivatives and hedging (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019	Dec. 31, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Amounts reclassified from accumulated other comprehensive income (loss)	$ 77	$ (172)	$ 261	$ (327)
Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount	30,500
Designated as Hedging Instrument \| Forward contracts
Derivative Instruments, Gain (Loss) [Line Items]
Notional amount			7,500	20,400
Fair value of outstanding forward contracts, asset	300		$ 179
Fair value of outstanding forward contracts, liability	$ 418			$ 598