Stock-Based Compensation - Schedule of Non-qualified Stock Options Granted (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
May 31, 2020	May 31, 2019	May 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted	101	96	90
Weighted average exercise price, per share	$ 38.91	$ 42.86	$ 47.76
Weighted average grant date fair value, per share	$ 10.21	$ 12.54	$ 14.99
Stock-based compensation	$ 11,883	$ 11,733	$ 13,758
Non-Qualified Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	$ 1,029	$ 1,199	$ 1,203

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
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-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
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-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 718
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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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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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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-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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