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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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Amount of liabilities assumed at the acquisition date.

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Amount before accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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-Glossary Investing Activities

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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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Acquisitions (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended			0 Months Ended		0 Months Ended
	May 31, 2014	May 31, 2013	May 31, 2012	Jan. 03, 2012 International Segment [Member]	Jan. 03, 2012 International Segment [Member]	Feb. 08, 2012 Classroom and Supplemental Materials Publishing [Member]	Feb. 08, 2012 Classroom and Supplemental Materials Publishing [Member]
Business Acquisition [Line Items]
Acquisition related payments	$ 1.0	$ 0.3	$ 9.5	$ 3.0
Goodwill	178.7	178.7	178.5		1.5		1.4
Cash paid to acquire business						2.0
Liabilities assumed							4.8
Intangible assets acquired							$ 5.4