Other Income, Net (Other Income, Net) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2015	Mar. 31, 2014
Other Income, Net [Abstract]
Interest income on corporate funds	$ (7.2)us-gaap_InvestmentIncomeInterest	$ (6.1)us-gaap_InvestmentIncomeInterest	$ (43.9)us-gaap_InvestmentIncomeInterest	$ (40.7)us-gaap_InvestmentIncomeInterest
Realized gains on available-for-sale securities	(1.0)	(2.2)	(3.6)	(19.7)
Realized losses on available-for-sale securities	0.3	0.7	1.3	3.2
Gain on the sale of notes receivable	0us-gaap_GainLossOnSaleOfNotesReceivable	0us-gaap_GainLossOnSaleOfNotesReceivable	(1.4)us-gaap_GainLossOnSaleOfNotesReceivable	0us-gaap_GainLossOnSaleOfNotesReceivable
Other income, net	$ (7.9)us-gaap_NonoperatingIncomeExpense	$ (7.6)us-gaap_NonoperatingIncomeExpense	$ (47.6)us-gaap_NonoperatingIncomeExpense	$ (57.2)us-gaap_NonoperatingIncomeExpense

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This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 9

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27357-111563

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- Definition

This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

+ References

+ Details

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- Definition

Reflects the net positive or negative amount derived from subtracting from net proceeds of sale the carrying amounts, net of allocated reserves, of notes receivable transferred to a third party in a transaction that qualifies for sales treatment.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 20

-Section 50

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=13989330&loc=d3e107425-111719

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- Definition

Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.7(b))

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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- Definition

The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.7)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Article 5

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