Annual increase in ordinary shares for available for future issuance.

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Annual increase in shares for available for future issuance by percentage of outstanding ordinary shares as of last day of immediately preceding fiscal year.

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- Definition

Annual increase in shares for available for future issuance by percentage of the outstanding ordinary shares on the first day of such fiscal year.

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- Definition

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

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- Definition

Ownership percentage of voting power.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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No definition available.

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Unrecognized cost of unvested options awarded to employees as compensation.

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No definition available.

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Description of award terms as to how many shares or portion of an award are no longer contingent on satisfaction of either a service condition, market condition or a performance condition, thereby giving the employee the legal right to convert the award to shares, to sell the shares, and be entitled to the cash proceeds of such sale. For example, vesting may be expressed as being 25 percent of the shares under option on each anniversary of the grant date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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.

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- Definition

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Number of additional shares authorized for issuance under an established share-based compensation plan.

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Intrinsic value of equity-based compensation awards not vested. Excludes stock and unit options.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-Paragraph 2
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Purchase price of common stock expressed as a percentage of its fair value.

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Employee Benefits and Stock-based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions			12 Months Ended
	Feb. 02, 2016	Feb. 02, 2015	Jan. 31, 2017	Jan. 31, 2016	Jan. 31, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Closing price of ordinary shares			$ 49.61
2012 Equity Incentive Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Voting power of all classes of company's shares			10.00%
Additional ordinary shares reserved for issuance	1,455,001	1,387,689
2012 Equity Incentive Plan [Member] \| Scenario, plan automatically increased by the lessor of [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Annual increase in ordinary shares for available for future issuance	3,500,000	3,500,000
Annual shares increase for future issuance by percentage under 2012 equity incentive plan	4.50%	4.50%
Amended and Restated 2012 Employee Stock Purchase Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Purchase price of ordinary shares, percentage			85.00%	85.00%	85.00%
Additional ordinary shares reserved for issuance	404,166	385,469
Percentage of salary contribution by employees			15.00%
Amended and Restated 2012 Employee Stock Purchase Plan [Member] \| Scenario, plan automatically increased by the lessor of [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Annual increase in ordinary shares for available for future issuance	1,500,000	1,500,000
Annual shares increase for future issuance by percentage under 2012 employee stock purchase plan	1.25%	1.25%
Stock options [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total unrecognized compensation cost, stock options			$ 8.1
Weighted average recognition period			1 year 11 months 9 days
Stock options [Member] \| 2012 Equity Incentive Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Option's term of up to 10 years from grant date			10 years	10 years	10 years
Vesting schedule			Vest 25% on the first anniversary service date of the grant and remainder vest ratably over the following 36 months.
Stock options [Member] \| Incentive stock options granted to 10% ownership [Member] \| Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Purchase price of ordinary shares, percentage			110.00%
Stock options [Member] \| Non statutory stock options and incentive stock options granted to less than 10% ownership [Member] \| Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Purchase price of ordinary shares, percentage			100.00%
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			$ 107.9
Total fair value of vesting dates of restricted stock and restricted stock units vested			$ 51.1	$ 59.2	$ 17.3
Restricted Stock and Restricted Stock Units [Member] \| 2012 Equity Incentive Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting schedule			1/4th of the shares on the first anniversary service date of the grant and 1/16th of the shares vest every 3 months thereafter, so as to be 100% vested on the fourth anniversary of the vesting commencement date
Restricted stock units [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted average recognition period			2 years 9 months 18 days
Total unrecognized compensation cost, restricted stock units			$ 104.1
Restricted Stock Awards [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted average recognition period			1 year 8 months 23 days
Total unrecognized compensation cost, restricted stock awards			$ 6.9