Amount of expense (reclass) for award under share-based payment arrangement.

No definition available.

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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No definition available.

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

+ References

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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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- References

No definition available.

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

Net 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.

+ References

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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

+ References

No definition available.

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- Definition

Expected term of 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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.D.2)
-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

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Accounting for Stock-Based Compensation (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended		3 Months Ended			9 Months Ended
	Jul. 31, 2019	Jun. 30, 2019	Feb. 29, 2020	Aug. 31, 2019	Feb. 28, 2019	Feb. 29, 2020	Feb. 28, 2019
Stock options, additional disclosures
Compensation expense						$ 1.1	$ 8.3
Restricted stock
Stock options, additional disclosures
Compensation expense			$ 2.3		$ 2.7	7.2	5.7
Performance-based restricted stock
Stock options, additional disclosures
Granted (in shares)				52,475
Granted (in dollars per share)				$ 37.66
Time-based restricted stock
Stock options, additional disclosures
Granted (in shares)				56,535
Granted (in dollars per share)				$ 37.66
Time-based restricted stock \| Board of Directors
Stock options, additional disclosures
Granted (in shares)		43,142
Granted (in dollars per share)		$ 30.60
Stock options
Stock options, additional disclosures
Granted (in shares)	414,460
Granted (in dollars per share)	$ 37.66
Weighted average fair value of stock options granted (in dollars per share)	$ 10.30
Total intrinsic value of stock options exercised						6.2	12.0
Compensation expense			$ 0.9		$ 1.0	$ 3.1	$ 3.2
Assumptions used in the Black-Scholes option pricing models to estimate the fair value of each stock option grant
Risk-free interest rate	1.90%
Expected volatility of common stock	32.00%
Dividend yield	0.80%
Expected option term in years	4 years 6 months