Closing market price of ordinary shares on NASDAQ on the last day of reporting period.

No definition available.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5047-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

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- Definition

Amount of cost to be recognized for option under share-based payment arrangement.

+ References

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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

Intrinsic value of nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

No definition available.

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Stock-based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2019	Jul. 31, 2018	Jul. 31, 2019	Jul. 31, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation	$ 16,200	$ 15,130	$ 32,660	$ 29,325
Closing price of ordinary shares	$ 49.95		$ 49.95
Accrued and other current liabilities [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total stock-based compensation	$ 1,200		$ 2,200
Stock options [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total unrecognized compensation cost, stock options	3,800		$ 3,800
Weighted average recognition period			2 years 6 months 18 days
Restricted stock units [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total unrecognized compensation cost, restricted stock units	96,200		$ 96,200
Weighted average recognition period			2 years 5 months 1 day
Restricted Stock Awards [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted average recognition period			1 month 17 days
Total unrecognized compensation cost, restricted stock awards	100		$ 100
Restricted Stock and Restricted Stock Units [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Aggregate intrinsic value of unvested restricted stock and restricted stock units	$ 114,800		$ 114,800