Leases - ASC 842 Minimum Lease Payments (Details) - USD ($) $ in Thousands	Jul. 31, 2020	Jan. 31, 2020	Jul. 31, 2019
Leases [Abstract]
Remaining of 2021	$ 2,942
2022	5,757
2023	5,323
2024	5,225
2025	5,370
Thereafter	1,350
Remaining balance of lease payments	25,967
Short-term lease liabilities	4,581	$ 3,654	$ 3,275
Long-term lease liabilities	17,798	$ 19,787	$ 21,598
Total lease liabilities	22,379
Difference between undiscounted cash flows and discounted cash flows	$ 3,588