Equity Compensation Plans - Additional Information (Detail) - USD ($)	3 Months Ended
Aug. 31, 2022	Aug. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average fair value per share of stock options granted	$ 8.49
Compensation expense related to share based awards	$ 1,867,000	$ 1,690,000
Options, Granted	0
2018 Omnibus Incentive Plan \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	3 years 9 months 18 days
Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount	$ 6,442,000
Employee Stock Purchase Plan \| 2011 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual maximum limit percentage of compensation to purchase shares	5.00%
Employee stock purchase plan stock price percentage	10.00%
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option vesting period	3 years
Stock option contractual terms	5 years
Minimum \| 2018 Omnibus Incentive Plan \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option vesting period	3 years
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option vesting period	5 years
Stock option contractual terms	10 years
Maximum \| 2018 Omnibus Incentive Plan \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option vesting period	5 years

Employee Purchase Plan Purchase Price Percentage of Fair Market Value

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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Section 50
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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Discount rate from fair value on purchase date that participants pay for shares.

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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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Gross number of share options (or share units) granted during the period.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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-Publisher FASB
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Amount of cost expensed and capitalized for award under share-based payment arrangement.

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