For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets.

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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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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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Business Segment Information (Details 4) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	May. 31, 2015	Feb. 28, 2015	Nov. 30, 2014	Aug. 31, 2014	May. 31, 2014	Feb. 28, 2014	Nov. 30, 2013	Aug. 31, 2013	May. 31, 2015	May. 31, 2014	May. 31, 2013
Business Segment Information
Long-lived assets	$ 560.9				$ 1,082.6				$ 560.9	$ 1,082.6
Sales	415.8	$ 380.1	$ 403.3	$ 395.1	420.6	$ 399.8	$ 458.9	$ 429.8	1,594.3	1,709.1	$ 1,807.9
United States
Business Segment Information
Long-lived assets	523.8				809.0				523.8	809.0
Europe
Business Segment Information
Long-lived assets	37.0				271.4				37.0	271.4
Other
Business Segment Information
Long-lived assets	$ 0.1				$ 2.2				0.1	2.2
Foreign countries
Business Segment Information
Sales									$ 536.5	$ 456.0	$ 464.9
Foreign countries \| Total sales \| Geographic concentration
Business Segment Information
Percentage of total sales									33.70%	26.70%	25.70%