CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	2026 Notes	2023 Notes	2025 Notes	Common Stock	Common Stock 2023 Notes	Additional Paid-In Capital	Additional Paid-In Capital 2026 Notes	Additional Paid-In Capital 2023 Notes	Additional Paid-In Capital 2025 Notes	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit
Balance at Jan. 31, 2019	$ 313,281				$ 6		$ 567,797				$ 335	$ (254,857)
Balance, shares at Jan. 31, 2019					60,455,381
Cancellation of common stock issued from acquisitions, shares					(7,784)
Issuance of common stock for employee share purchase plan	5,396						5,396
Issuance of common stock for employee share purchase plan, shares					108,758
Exercise of stock options	10,542				$ 1		10,541
Exercise of stock options, shares					1,639,521
Stock-based compensation expense	38,654						38,654
Vested restricted stock units, shares					531,282
Equity component of Notes, net of issuance costs				$ 246,967						$ 246,967
Purchase of capped calls in relation to Notes				(118,738)						(118,738)
Other comprehensive income (loss)	(1,568)										(1,568)
Net loss	(40,462)											(40,462)
Balance at Jul. 31, 2019	454,072				$ 7		750,617				(1,233)	(295,319)
Balance, shares at Jul. 31, 2019					62,727,158
Balance at Apr. 30, 2019	319,166				$ 7		594,735				(251)	(275,325)
Balance, shares at Apr. 30, 2019					61,640,573
Exercise of stock options	6,060						6,060
Exercise of stock options, shares					783,226
Stock-based compensation expense	21,593						21,593
Vested restricted stock units, shares					303,359
Equity component of Notes, net of issuance costs				246,967						246,967
Purchase of capped calls in relation to Notes				$ (118,738)						$ (118,738)
Other comprehensive income (loss)	(982)										(982)
Net loss	(19,994)											(19,994)
Balance at Jul. 31, 2019	454,072				$ 7		750,617				(1,233)	(295,319)
Balance, shares at Jul. 31, 2019					62,727,158
Balance at Jan. 31, 2020	445,657				$ 7		790,468				871	(345,689)
Balance, shares at Jan. 31, 2020					64,528,970
Issuance of common stock for acquisitions	41,841						41,841
Issuance of common stock for acquisitions, shares					432,634
Issuance of common stock for employee share purchase plan	7,391						7,391
Issuance of common stock for employee share purchase plan, shares					104,818
Exercise of stock options	9,609						9,609
Exercise of stock options, shares					987,804
Stock-based compensation expense	58,756						58,756
Vested restricted stock units, shares					658,285
Equity component of Notes, net of issuance costs		$ 501,053						$ 501,053
Purchase of capped calls in relation to Notes		(192,786)						(192,786)
Settlement of Notes			$ (384,414)						$ (384,414)
Settlement of Notes, shares						2,065,832
Deferred tax related to convertible senior notes	(9,588)						(9,588)
Temporary equity reclassification	(133)						(133)
Other comprehensive income (loss)	7,462										7,462
Net loss	(57,932)											(57,932)
Balance at Jul. 31, 2020	426,916				$ 7		822,197				8,333	(403,621)
Balance, shares at Jul. 31, 2020					68,778,343
Balance at Apr. 30, 2020	465,122				$ 7		822,713				2,907	(360,505)
Balance, shares at Apr. 30, 2020					66,827,590
Issuance of common stock for acquisitions	41,841						41,841
Issuance of common stock for acquisitions, shares					395,066
Exercise of stock options	6,381						6,381
Exercise of stock options, shares					582,946
Stock-based compensation expense	34,209						34,209
Vested restricted stock units, shares					360,130
Equity component of Notes, net of issuance costs		501,053						501,053
Purchase of capped calls in relation to Notes		$ (192,786)						$ (192,786)
Settlement of Notes			$ (382,245)						$ (382,245)
Settlement of Notes, shares						612,611
Deferred tax related to convertible senior notes	(9,588)						(9,588)
Temporary equity reclassification	619						619
Other comprehensive income (loss)	5,426										5,426
Net loss	(43,116)											(43,116)
Balance at Jul. 31, 2020	$ 426,916				$ 7		$ 822,197				$ 8,333	$ (403,621)
Balance, shares at Jul. 31, 2020					68,778,343