The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

Goodwill and Other Intangibles - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Feb. 28, 2018	Aug. 31, 2017	Feb. 28, 2018	Feb. 28, 2017	May 31, 2016
Goodwill and Other Intangibles (Details) [Line Items]
Amortizable intangible assets acquired			$ 1.5	$ 0.2	$ 7.0
Amortization expense			$ 1.6	$ 1.8	$ 2.5
Useful life			4 years 2 months
U.K. Based Book Business [Member]
Goodwill and Other Intangibles (Details) [Line Items]
Amortizable intangible assets acquired	$ 1.4
U.S. Based Book Fair Business
Goodwill and Other Intangibles (Details) [Line Items]
Amortizable intangible assets acquired		$ 0.1