Goodwill and Intangible Assets, Net - Schedule Intangible Assets, Net (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jul. 31, 2020	Jul. 31, 2019	Jul. 31, 2020	Jul. 31, 2019	Jan. 31, 2020	Jan. 31, 2019
Intangible Assets, Gross [Roll Forward]
Beginning of period			$ 25,227	$ 1,900	$ 1,900
Identifiable Intangible Assets Acquired			18,165		23,327
End of period	$ 43,392		43,392		25,227
Accumulated Amortization [Roll Forward]
Beginning of period			(3,921)	(1,594)	(1,594)
Amortization of Intangible Assets	(2,100)	$ (300)	(3,534)	(400)	(2,327)
End of period	(7,455)		(7,455)		(3,921)
Intangible assets, net	35,937		35,937		21,306	$ 306
Developed technology
Intangible Assets, Gross [Roll Forward]
Beginning of period			18,670	1,900	1,900
Identifiable Intangible Assets Acquired			10,731		16,770
End of period	29,401		29,401		18,670
Accumulated Amortization [Roll Forward]
Beginning of period			(3,473)	(1,594)	(1,594)
Amortization of Intangible Assets			(2,415)		(1,879)
End of period	(5,888)		(5,888)		(3,473)
Intangible assets, net	23,513		$ 23,513		$ 15,197	306
Intangible assets, estimated useful life			4 years 3 months 18 days		4 years 6 months
Customer relationships
Intangible Assets, Gross [Roll Forward]
Beginning of period			$ 5,237	0	$ 0
Identifiable Intangible Assets Acquired			6,743		5,237
End of period	11,980		11,980		5,237
Accumulated Amortization [Roll Forward]
Beginning of period			(351)	0	0
Amortization of Intangible Assets			(938)		(351)
End of period	(1,289)		(1,289)		(351)
Intangible assets, net	10,691		$ 10,691		$ 4,886	0
Intangible assets, estimated useful life			4 years 6 months		4 years 8 months 12 days
Trademarks
Intangible Assets, Gross [Roll Forward]
Beginning of period			$ 1,320	0	$ 0
Identifiable Intangible Assets Acquired			691		1,320
End of period	2,011		2,011		1,320
Accumulated Amortization [Roll Forward]
Beginning of period			(97)	$ 0	0
Amortization of Intangible Assets			(181)		(97)
End of period	(278)		(278)		(97)
Intangible assets, net	$ 1,733		$ 1,733		$ 1,223	$ 0
Intangible assets, estimated useful life			4 years 3 months 18 days		4 years 7 months 6 days