Notes Payable, Long-Term Debt and Capital Lease Obligations (Fair Value) (Details 4) $ in Millions	May 31, 2017 USD ($)
8.250% Senior Notes Due 2018
Debt Instrument [Line Items]
Estimated fair value of senior notes	$ 419.1
5.625% Senior Notes Due 2020
Debt Instrument [Line Items]
Estimated fair value of senior notes	433.9
4.700% Senior Notes due 2022
Debt Instrument [Line Items]
Estimated fair value of senior notes	531.9
4.900% Senior Notes due 2023
Debt Instrument [Line Items]
Estimated fair value of senior notes	$ 313.1

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13433-108611

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13476-108611

Name:	us-gaap_DebtInstrumentFairValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant