CONSOLIDATED STATEMENTS OF CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS' EQUITY (DEFICIT) - USD ($) $ in Thousands	Total	Convertible Preferred Stock	Series F convertible preferred stock	Series E preferred stock warrants	Series G convertible preferred stock	Common Stock	Common Stock Series E preferred stock warrants	Additional Paid-In Capital	Additional Paid-In Capital Series E preferred stock warrants	Accumulated Deficit
Balance at Jan. 31, 2014	$ (47,619)					$ 1		$ 1,793		$ (49,413)
Balance, shares at Jan. 31, 2014						3,067,348
Balance at Jan. 31, 2014		$ 48,472
Balance, shares at Jan. 31, 2014		23,543,199
Issuance of convertible preferred stock, net of issuance costs			$ 39,972
Issuance of convertible preferred stock, net of issuance costs, shares			4,944,371
Exercise of stock options	410							410
Exercise of stock options, shares						1,136,298
Vesting of early exercised stock options	86							86
Stock-based compensation expense	1,854							1,854
Net loss	(27,300)									(27,300)
Balance at Jan. 31, 2015	(72,569)					$ 1		4,143		(76,713)
Balance, shares at Jan. 31, 2015						4,203,646
Balance at Jan. 31, 2015		$ 88,444
Balance, shares at Jan. 31, 2015		28,487,570
Issuance of convertible preferred stock, net of issuance costs					$ 75,731
Issuance of convertible preferred stock, net of issuance costs, shares					4,783,762
Exercise of Series E preferred stock warrants				$ 775
Exercise of Series E preferred stock warrants, shares				160,523
Issuance of common stock for acquisitions	1,269							1,269
Issuance of common stock for acquisitions, shares						314,386
Exercise of stock options	477							477
Exercise of stock options, shares						1,240,306
Vesting of early exercised stock options	142							142
Stock-based compensation expense	10,598							10,598
Net loss	(46,156)									(46,156)
Balance at Jan. 31, 2016	(106,239)					$ 1		16,629		(122,869)
Balance, shares at Jan. 31, 2016						5,758,338
Balance at Jan. 31, 2016	$ 164,950	$ 164,950
Balance, shares at Jan. 31, 2016	33,431,855	33,431,855
Exercise of Series E preferred stock warrants				$ 924					$ 924
Exercise of Series E preferred stock warrants, shares							36,971
Initial public offering, net of issuance costs	$ 137,113					$ 1		137,112
Initial public offering, net of issuance costs, shares						8,510,000
Issuance of common stock for acquisitions	2,357							2,357
Issuance of common stock for acquisitions, shares						150,545
Conversion of preferred stock	164,950					$ 3		164,947
Conversion of preferred stock, shares						34,610,979
Conversion of preferred stock		$ (164,950)
Conversion of preferred stock, shares		(33,431,855)
Exercise of stock options	2,186							2,186
Exercise of stock options, shares						1,184,708
Vesting of early exercised stock options	606							606
Stock-based compensation expense	9,551							9,551
Excess income tax benefit	51							51
Net loss	(37,607)									(37,607)
Balance at Jan. 31, 2017	$ 173,892					$ 5		$ 334,363		$ (160,476)
Balance, shares at Jan. 31, 2017						50,251,541
Balance, shares at Jan. 31, 2017	0