Income Taxes - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 31, 2020	Oct. 31, 2019	Oct. 31, 2020	Oct. 31, 2019
Income Tax Disclosure [Abstract]
Tax expense (benefit)	$ 209	$ 349	$ (626)	$ (2,285)
Pretax losses	$ (72,555)	$ (63,146)	$ (191,152)	$ (160,726)
Effective income tax rate	(0.30%)	(0.60%)	0.30%	1.40%