v3.21.1

Fair value measurements - Schedule of assets and liabilities measured at fair value (Detail) - Fair Value, Recurring - USD ($)	Jan. 31, 2021	Jan. 31, 2020
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Money market mutual funds	$ 197,522,000	$ 86,600,000
Foreign currency derivative contracts	148,000	58,000
Total assets	197,670,000	86,658,000
Acquisition related contingent consideration liabilities	(1,286,000)
Total liabilities	(1,286,000)
Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Money market mutual funds	197,522,000	86,600,000
Foreign currency derivative contracts	0	0
Total assets	197,522,000	86,600,000
Acquisition related contingent consideration liabilities	0
Total liabilities	0
Significant Other Observable Inputs (Level 2)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Money market mutual funds	0	0
Foreign currency derivative contracts	148,000	58,000
Total assets	148,000	58,000
Acquisition related contingent consideration liabilities	0
Total liabilities	0
Significant Unobservable Inputs (Level 3)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Money market mutual funds	0	0
Foreign currency derivative contracts	0	0
Total assets	0	$ 0
Acquisition related contingent consideration liabilities	(1,286,000)
Total liabilities	$ (1,286,000)

X

- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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X

- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

No definition available.

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- Definition

Fair value portion of arrangements with third parties, including, but not limited to, operating lease arrangement and arrangement in which the entity has agreed to expend funds to procure goods or services, or has agreed to commit resources to supply goods or services.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(25))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Fair value portion of asset contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward contracts, and swaps.

+ References

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- Definition

Fair value of financial and nonfinancial obligations.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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