Share based compensation arrangement by share based payment award, options, contractual term one.

No definition available.

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- Definition

The increase (decrease) during the reporting period in the amounts payable to taxing authorities for taxes that are based on the reporting entity's earnings, net of amounts receivable from taxing authorities for refunds of overpayments or recoveries of income taxes, and in deferred and other tax liabilities and assets.

+ References

No definition available.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ 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 (a)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

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

+ References

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=96867065&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.

+ References

No definition available.

+ Details

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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.

+ 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 (d)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

Amount of capitalized and expensed compensation cost from equity-based compensation arrangements.

+ 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 (h)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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Equity Compensation Plans - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Feb. 28, 2018	Feb. 28, 2017	Feb. 28, 2018	Feb. 28, 2017	May 31, 2018	May 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense related to share based awards	$ 1,026,000	$ 1,198,000	$ 3,692,000	$ 3,932,000
Weighted-average fair value per share of stock options granted						$ 11.84
During fiscal 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average fair value per share of stock options granted					$ 14.44
U.S. \| ASU No. 2016-09
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase (decrease) in income tax expense	$ 331,000		$ (3,463,000)
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%
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option vesting period			3 years
Stock option contractual terms			5 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