Goodwill and Intangible Assets, Net - Intangible Assets (Details) - USD ($) $ in Thousands	6 Months Ended
Jul. 31, 2019	Jan. 31, 2019
Finite-Lived Intangible Assets, Net [Abstract]
Weighted-average Remaining Useful Life (Years)	6 years 7 months 6 days
Estimated Fair Value	$ 114,610	$ 114,610
Accumulated Amortization	(50,180)	(41,027)
Acquisition-related intangibles, net, excluding cumulative translation adjustment	64,430	73,583
Cumulative translation adjustment	640	620
Acquisition-related Intangibles, Net	$ 65,070	74,203
Existing technology
Finite-Lived Intangible Assets, Net [Abstract]
Weighted-average Remaining Useful Life (Years)	2 years 1 month 6 days
Estimated Fair Value	$ 31,594	31,594
Accumulated Amortization	(23,112)	(20,747)
Acquisition-related intangibles, net, excluding cumulative translation adjustment	$ 8,482	10,847
Tradenames / trademarks
Finite-Lived Intangible Assets, Net [Abstract]
Weighted-average Remaining Useful Life (Years)	18 days
Estimated Fair Value	$ 2,419	2,419
Accumulated Amortization	(2,223)	(1,858)
Acquisition-related intangibles, net, excluding cumulative translation adjustment	$ 196	561
Customer contracts & related relationships
Finite-Lived Intangible Assets, Net [Abstract]
Weighted-average Remaining Useful Life (Years)	7 years 10 months 24 days
Estimated Fair Value	$ 65,782	65,782
Accumulated Amortization	(15,148)	(11,168)
Acquisition-related intangibles, net, excluding cumulative translation adjustment	$ 50,634	54,614
Certifications
Finite-Lived Intangible Assets, Net [Abstract]
Weighted-average Remaining Useful Life (Years)	1 year 1 month 6 days
Estimated Fair Value	$ 6,917	6,917
Accumulated Amortization	(5,538)	(4,846)
Acquisition-related intangibles, net, excluding cumulative translation adjustment	$ 1,379	2,071
Maintenance contracts & related relationships
Finite-Lived Intangible Assets, Net [Abstract]
Weighted-average Remaining Useful Life (Years)	27 days
Estimated Fair Value	$ 1,498	1,498
Accumulated Amortization	(1,254)	(1,104)
Acquisition-related intangibles, net, excluding cumulative translation adjustment	$ 244	394
Backlog—Subscription
Finite-Lived Intangible Assets, Net [Abstract]
Weighted-average Remaining Useful Life (Years)	1 year 2 months 12 days
Estimated Fair Value	$ 6,400	6,400
Accumulated Amortization	(2,905)	(1,304)
Acquisition-related intangibles, net, excluding cumulative translation adjustment	$ 3,495	$ 5,096

Finite-Lived Intangible Assets, Cumulative Translation Adjustment

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- Definition

Finite-Lived Intangible Assets, Net Excluding Cumulative Translation Adjustments

+ References

No definition available.

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- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 928
-SubTopic 340
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6473545&loc=d3e61844-108004

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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Remaining amortization period of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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