Business Segment Information - Reconcile of Gross Profit to Income (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Nov. 30, 2018	Nov. 30, 2017	Nov. 30, 2018	Nov. 30, 2017
Reconciliation of segment gross profit to income before provision for income taxes
Segment gross profit	$ 78.3	$ 70.7	$ 149.5	$ 132.3
Selling, general and administrative	(49.1)	(48.8)	(97.3)	(93.1)
Provision for doubtful accounts	(12.4)	(0.1)	(13.0)	(0.3)
Other income (expense), net	(0.2)		0.2
Interest expense	(2.5)	(1.9)	(4.6)	(3.6)
Interest income	0.1	0.1	0.6	0.1
Income from continuing operations before provision for income taxes	$ 14.2	$ 20.0	$ 35.4	$ 35.4

Sum of operating profit and nonoperating income (expense) before income taxes and noncontrolling interest.

No definition available.

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- Definition

The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses along with impairments. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

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No definition available.

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- Definition

Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

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- Definition

Amount of the cost of borrowed funds accounted for as interest expense.

+ References

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- Definition

Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

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Amount of income (expense) related to nonoperating activities, classified as other.

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- Definition

Amount of expense related to write-down of receivables to the amount expected to be collected. Includes, but is not limited to, accounts receivable and notes receivable.

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- References

No definition available.

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