v3.20.1

Income taxes - Components of Income tax (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Jan. 31, 2020	Oct. 31, 2019	Jul. 31, 2019	Apr. 30, 2019	Jan. 31, 2019	Oct. 31, 2018	Jul. 31, 2018	Apr. 30, 2018	Jan. 31, 2020	Jan. 31, 2019	Jan. 31, 2018
Current:
Federal									$ (448)	$ 1,095	$ 392
State									274	416	130
Total current tax provision (benefit)									(174)	1,511	522
Deferred:
Federal									3,538	1,258	4,068
State									127	(850)	237
Total deferred tax provision									3,665	408	4,305
Total income tax provision	$ (417)	$ (9,918)	$ 4,370	$ 9,456	$ 3,241	$ 1,745	$ (1,029)	$ (2,038)	$ 3,491	$ 1,919	$ 4,827

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