Income Taxes Effective Tax Rate Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2020	Jan. 31, 2019	Jan. 31, 2018
Income Tax Disclosure [Abstract]
U.S. federal tax (provision) benefit at statutory rate	$ 25,294	$ 15,669	$ 21,849
State taxes, net of federal (provision) benefit	4,124	6,499	1,766
Foreign tax rate differential	970	448	(637)
Non-deductible expenses	(2,967)	(1,737)	(3,503)
Change in valuation allowance	(24,377)	(37,808)	1,599
Rate change	(7,017)	7	(21,580)
Excess tax benefits from stock-based compensation	6,519	16,847	0
Return to provision adjustment	(2,323)	(337)	(93)
Other, net	(1,320)	190	437
Total (provision for) benefit from income taxes	$ (1,097)	$ (222)	$ (162)