Leases - Supplemental 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 finance lease	$ 884	$ 0
Operating cash flows from operating leases	1,297	1,032
Financing cash flows from finance lease	1,135	0
Right-of-use assets obtained in exchange for lease obligations:
Finance lease	0	0
Operating leases	$ 23,375	$ 2,269
Weighted-average remaining lease term (in years):
Finance lease	9 years 8 months 12 days	10 years 8 months 12 days
Operating leases	8 years 8 months 12 days	4 years 9 months 18 days
Weighted-average discount rate:
Finance lease	5.60%	5.60%
Operating leases	5.00%	6.10%