Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) shares in Thousands, $ in Thousands	Jul. 31, 2019	Jan. 31, 2019
Accounts receivable, allowance for doubtful accounts	$ 1,000	$ 1,000
Redeemable preferred stock, par value (in dollars per share)	$ 0.0005	$ 0.0005
Redeemable preferred stock, shares authorized (in shares)	0	137,419
Redeemable preferred stock, shares issued (in shares)	0	131,268
Redeemable preferred stock, shares outstanding (in shares)	0	131,268
Redeemable preferred stock, liquidation preference	$ 0	$ 545,000
Preferred stock, par value (in dollars per share)	$ 0.0005	$ 0.0005
Preferred stock, shares authorized (in shares)	100,000	0
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.0005	$ 0.0005
Common stock, shares authorized (in shares)	0	220,000
Common stock, shares issued (in shares)	0	47,421
Common stock, shares outstanding (in shares)	0	47,421
Class A common stock
Common stock, par value (in dollars per share)	$ 0.0005	$ 0.0005
Common stock, shares authorized (in shares)	2,000,000	0
Common stock, shares issued (in shares)	20,700	0
Common stock, shares outstanding (in shares)	20,700	0
Class B common stock
Common stock, par value (in dollars per share)	$ 0.0005	$ 0.0005
Common stock, shares authorized (in shares)	300,000	0
Common stock, shares issued (in shares)	205,193	0
Common stock, shares outstanding (in shares)	205,193	0