Leases - Supplemental Balance Sheet Information (Details) - USD ($) $ in Thousands	Jul. 31, 2020	Jan. 31, 2020	Apr. 30, 2019
Assets
Operating lease right-of-use assets	$ 1,636	$ 2,300	$ 3,000
Liabilities
Total operating lease liabilities	1,636	2,300	3,000
Current liabilities	613	1,339
Non-current liabilities	1,023	961
Total Operating lease liabilities	$ 1,636	$ 2,300	$ 3,000
Weighted average remaining lease term (years)
Operating leases	1 year 6 months 25 days	1 year 9 months 3 days
Weighted average discount rate:
Operating leases	9.27%	9.27%