Intangible Assets Amortization (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jul. 31, 2020	Jan. 31, 2020
Finite-Lived Intangible Assets
Gross Fair Value	$ 341,610	$ 341,610
Accumulated Amortization	(132,486)	(103,195)
Total	209,124	238,415
Developed technology
Finite-Lived Intangible Assets
Gross Fair Value	252,530	252,530
Accumulated Amortization	(107,712)	(87,112)
Total	$ 144,818	$ 165,418
Weighted Average Remaining Useful Life	65 months	68 months
Customer relationships
Finite-Lived Intangible Assets
Gross Fair Value	$ 81,810	$ 81,810
Accumulated Amortization	(20,403)	(12,403)
Total	$ 61,407	$ 69,407
Weighted Average Remaining Useful Life	47 months	53 months
Other acquired intangible assets
Finite-Lived Intangible Assets
Gross Fair Value	$ 7,270	$ 7,270
Accumulated Amortization	(4,371)	(3,680)
Total	$ 2,899	$ 3,590
Weighted Average Remaining Useful Life	26 months	32 months