Accrued share based compensation expense.

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- Definition

Number of additional shares reserved for issuance under an established employee stock purchase plan.

+ References

No definition available.

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- Definition

Annual increase in ordinary shares for available for future issuance.

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No definition available.

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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.

+ References

No definition available.

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- Definition

Closing market price of stock on NASDAQ on last day of reporting period.

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No definition available.

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- Definition

Maximum number of ordinary shares reserved for issuance.

+ References

No definition available.

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- Definition

Number of shares authorized for issuance under the equity incentive plan.

+ References

No definition available.

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- Definition

Ownership percentage of voting power.

+ References

No definition available.

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- Definition

Amount of cost for defined contribution plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
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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

Description of service or performance condition required to be met for earning right to award under share-based payment arrangement. Includes, but is not limited to, combination of market, performance or service condition.

+ References

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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.

+ 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

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://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Number of additional shares authorized for issuance under share-based payment arrangement.

+ 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.

+ Details

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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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- Definition

Purchase price of common stock expressed as a percentage of its fair value.

+ References

No definition available.

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Employee Benefits and Stock-based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended		2 Months Ended	3 Months Ended		12 Months Ended
	Nov. 30, 2021	Jun. 30, 2021	Jun. 30, 2021	Apr. 30, 2021	Apr. 30, 2020	Jan. 31, 2022	Jan. 31, 2021	Jan. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Contribution expense						$ 0.6
Accrued share based compensation expense						$ 7.8
Closing price of stock						$ 140.15
Stock options [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total unrecognized compensation cost, stock options						$ 27.7
Weighted average recognition period						2 years 6 months 10 days
Restricted Stock and Restricted Stock Units [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total fair value of vesting dates of restricted stock and restricted stock units vested						$ 192.5	$ 69.0	$ 52.1
Restricted stock units [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted average recognition period						2 years 3 months 25 days
Total unrecognized compensation cost, restricted stock units						$ 194.4
Aggregate intrinsic value of unvested restricted stock units						$ 371.6
2021 Equity Incentive Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Ordinary shares reserved for issuance		1,350,000
Maximum number of ordinary shares reserved for issuance		6,834,208	6,834,208
2012 Equity Incentive Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Additional ordinary shares reserved for issuance			0	1,599,634	1,521,252
Voting power of all classes of company's shares						10.00%
2012 Equity Incentive Plan [Member] \| Stock options [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 the remainder vest ratably over the following 36 months.
2012 Equity Incentive Plan [Member] \| Restricted Stock and Restricted Stock Units [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
2017 Stock Option Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Additional ordinary shares reserved for issuance	0
Incentive stock options granted to 10% ownership [Member] \| Stock options [Member] \| Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Purchase price of ordinary shares, percentage						110.00%
Non statutory stock options and incentive stock options granted to less than 10% ownership [Member] \| Stock options [Member] \| Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Purchase price of ordinary shares, percentage							100.00%
ESPP [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Purchase price of ordinary shares, percentage						85.00%	85.00%	85.00%
Percentage of salary contribution by employees						15.00%
Additional ordinary shares reserved for issuance				444,343	422,570
ESPP [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%