Discontinued Operations - Narrative (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended
Nov. 30, 2014 buyer transactions	Nov. 30, 2013
Discontinued Operations and Disposal Groups [Abstract]
Number of transactions involved in sale of business	3
Number of buyers involved in sale of business	3
Cash proceeds received, net of cash contributed	$ 153,996	$ 0

This element represents the cash inflow during the period from the sale of a component of the entity.

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 12

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3179-108585

Name:	us-gaap_ProceedsFromDivestitureOfBusinessesNetOfCashDivested
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration