Financial Data By Segment (Financial Data By Strategic Business Unit Segment) (Details) - USD ($) $ in Millions	3 Months Ended
Sep. 30, 2016	Sep. 30, 2015
Segment Reporting Information [Line Items]
Revenues from Continuing Operations	$ 2,916.9	$ 2,714.0
Earnings from Continuing Operations before Income Taxes	528.7	505.0
Employer Services
Segment Reporting Information [Line Items]
Revenues from Continuing Operations	2,261.2	2,130.8
Earnings from Continuing Operations before Income Taxes	656.6	570.3
PEO Services
Segment Reporting Information [Line Items]
Revenues from Continuing Operations	794.7	701.5
Earnings from Continuing Operations before Income Taxes	107.1	88.3
Other
Segment Reporting Information [Line Items]
Revenues from Continuing Operations	(3.6)	10.7
Earnings from Continuing Operations before Income Taxes	(99.6)	(24.6)
Client fund interest
Segment Reporting Information [Line Items]
Revenues from Continuing Operations	(135.4)	(129.0)
Earnings from Continuing Operations before Income Taxes	$ (135.4)	$ (129.0)

Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h)(1)(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ 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 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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