Income taxes - Schedule of Components of Income (Loss) Before Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2020	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Domestic	$ (21,673)		$ 24,479	$ 17,405	$ 22,409
Foreign	500		(410)	551	60
Income (loss) before provision for income taxes	$ (21,173)	$ 1,123	$ 24,069	$ 17,956	$ 22,469

The portion of earnings or loss from continuing operations before income taxes that is attributable to domestic operations.

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- Definition

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

+ References

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- Definition

The portion of earnings or loss from continuing operations before income taxes that is attributable to foreign operations, which is defined as Income or Loss generated from operations located outside the entity's country of domicile.

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