Other Income, Net (Other Income, Net) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2017	Dec. 31, 2016
Other Income and Expenses [Abstract]
Interest income on corporate funds	$ (22.7)	$ (21.3)	$ (48.5)	$ (44.3)
Realized gains on available-for-sale securities	(0.2)	(2.0)	(0.5)	(2.5)
Realized losses on available-for-sale securities	1.2	0.7	1.6	1.1
Gain on sale of assets	0.0	0.0	0.4	0.0
Gain on Disposition of CHSA/COBRA	0.0	205.4	0.0	205.4
Other income, net	$ (21.7)	$ (228.0)	$ (47.8)	$ (251.1)

Gain on Disposition of CHSA/COBRA

No definition available.

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- Definition

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=73527792&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=64830801&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 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=63488584&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=63488584&loc=d3e20235-122688

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- References

No definition available.

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