Employee Benefit Plans (Details) (USD $) In Millions	12 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2009
Employee Benefit Plans
Defined Contribution Savings Plan costs recorded	$ 18.8	$ 18.2	$ 15.9
Supplemental Officer Retirement Plan expense incurred	$ 1.6	$ 1.2	$ 0.6

The amount of costs recognized during the period for non-pension postretirement benefits, such as medical, dental and life insurance.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (q)
-URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e1928-114920

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph h
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5, 11
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585

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Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration