Acquisitions, Goodwill and Intangible Assets (Details Textual) - USD ($) $ in Thousands				3 Months Ended		6 Months Ended
	Nov. 01, 2019	Oct. 01, 2019	Sep. 13, 2019	Jul. 31, 2020	Jul. 31, 2019	Jul. 31, 2020	Jul. 31, 2019	Jan. 31, 2020
Business Acquisition
Common stock, shares issued				160,387,959		160,387,959		157,787,548
Goodwill				$ 1,292,840		$ 1,292,840		$ 1,292,840
Amortization of intangible assets				$ 14,600	$ 7,100	$ 29,300	$ 14,200
SignalFx
Business Acquisition
Percentage of voting interests acquired		100.00%
Purchase price		$ 961,400
Purchase price paid in cash		619,100
Fair value of replacement equity awards attributable to pre-acquisition service		$ 324,500
Common stock, shares issued		2,771,482
Fair value of replacement equity awards attributable to pre-acquisition service		$ 17,800
Acquired fair value of finite-lived intangible assets		173,700
Net assets acquired		62,100
Net deferred tax liabilities assumed		3,300
Goodwill		728,900
Replacement equity awards		$ 104,700
Omnition
Business Acquisition
Percentage of voting interests acquired			100.00%
Purchase price			$ 52,500
Purchase price paid in cash			31,600
Fair value of replacement equity awards attributable to pre-acquisition service			$ 20,200
Common stock, shares issued			176,989
Fair value of replacement equity awards attributable to pre-acquisition service			$ 700
Acquired fair value of finite-lived intangible assets			8,000
Goodwill			44,500
Replacement equity awards			$ 36,600
Streamlio
Business Acquisition
Percentage of voting interests acquired	100.00%
Purchase price	$ 19,800
Purchase price paid in cash	18,700
Fair value of replacement equity awards attributable to pre-acquisition service	1,100
Acquired fair value of finite-lived intangible assets	3,600
Net assets acquired	100
Goodwill	16,100
Replacement equity awards	$ 4,200