Leases - Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Apr. 30, 2020	Apr. 30, 2019
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$ (293)	$ (288)
Right-of-use assets obtained in exchange for lease liabilities:
Operating leases	$ 293	$ 592