Number of countries contributes more than concentration threshold.

No definition available.

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- Definition

Revenue from contract with customer.

+ References

No definition available.

+ Details

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
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-SubTopic 10
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-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118944033&loc=SL49130531-203044

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-Publisher FASB
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+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 8
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+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
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-Paragraph 13
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+ Details

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- Definition

Percentage of remaining performance obligation to total remaining performance obligation not recognized as revenue.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130556-203045

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- Details

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- Details

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- Details

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Revenues - Additional Information (Details) $ in Millions	3 Months Ended
Revenues - Additional Information (Details) $ in Millions	Apr. 30, 2020 USD ($)	Apr. 30, 2019 USD ($) Country	Jan. 31, 2020 USD ($)
Revenue from Contract with Customer [Line Items]
Deferred revenue	$ 368.3		$ 423.8
Deferred revenue, revenue recognized out of beginning balance	154.4	$ 134.4
Remaining performance obligation, revenue expected to be recognized	$ 722.7
Revenue remaining performance obligation, percentage	65.00%
Customer Concentration Risk \| Revenue
Revenue from Contract with Customer [Line Items]
Concentration risk percentage	10.00%	10.00%
Customer Concentration Risk \| United States \| Revenue
Revenue from Contract with Customer [Line Items]
Concentration risk percentage	73.00%	76.00%
Customer Concentration Risk \| Japan \| Revenue
Revenue from Contract with Customer [Line Items]
Concentration risk percentage	13.00%
Customer Concentration Risk \| Outside United States \| Revenue
Revenue from Contract with Customer [Line Items]
Number of countries outside domestic that contributes more than concentration threshold \| Country		0