Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2021	Feb. 02, 2020		Jan. 31, 2019
Statement of Comprehensive Income [Abstract]
Net loss	$ (282,076)	$ (200,987)		$ (178,362)	[1],[2]
Other comprehensive income, net of tax:
Unrealized net gains on available-for-sale securities	3,213	6,510		1,562
Reclassification adjustment for net (gains) losses on available-for-sale securities included in net loss	(1,252)	(723)		17
Change in unrealized net gains on available-for-sale securities	1,961	5,787	[1]	1,579	[1]
Comprehensive loss	$ (280,115)	$ (195,200)	[1]	$ (176,783)	[1]

[1]

[2]