Statements of Stockholders' Equity - USD ($) shares in Millions, $ in Millions	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Treasury Stock [Member]	AOCI Attributable to Parent [Member]
Common stock, shares issued, beginning of period at Jun. 30, 2014		638.7
Stockholders' Equity, balance, beginning of period at Jun. 30, 2014		$ 63.9	$ 545.2	$ 13,632.9	$ (7,750.0)	$ 178.2
Increase (Decrease) in Stockholders' Equity [Roll Forward]
NET EARNINGS	$ 1,452.5		0.0		0.0	0.0
Other comprehensive (loss)			0.0	0.0	0.0	(350.6)
Stock-based compensation expense			112.8	0.0	0.0	0.0
Issuance relating to stock compensation plans			(67.8)	0.0	243.0	0.0
Tax benefit from stock compensation plans			73.1	0.0	0.0	0.0
Treasury Stock, Acquired			0.0	0.0	(1,611.4)	0.0
Other			0.0	(1,523.0)	0.0	(88.2)
Dividend received from CDK Global, Inc.	825.0		0.0	825.0	0.0	0.0
Dividends, Stock			0.0	(927.1)	0.0	0.0
Common stock, shares issued, end of period at Jun. 30, 2015		638.7
Stockholders' Equity, balance, end of period at Jun. 30, 2015		$ 63.9	663.3	13,460.3	(9,118.4)	(260.6)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
NET EARNINGS	1,492.5		0.0		0.0	0.0
Other comprehensive (loss)			0.0	0.0	0.0	45.5
Stock-based compensation expense			117.2	0.0	0.0	0.0
Issuance relating to stock compensation plans			(47.5)	0.0	182.5	0.0
Tax benefit from stock compensation plans			35.1	0.0	0.0	0.0
Treasury Stock, Acquired			0.0	0.0	(1,202.7)	0.0
Other			0.0	6.2	0.0	0.0
Dividend received from CDK Global, Inc.	$ 0.0
Dividends, Stock			0.0	(955.7)	0.0	0.0
Common stock, shares issued, end of period at Jun. 30, 2016	638.7	638.7
Stockholders' Equity, balance, end of period at Jun. 30, 2016		$ 63.9	768.1	14,003.3	(10,138.6)	(215.1)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
NET EARNINGS	$ 1,733.4		0.0		0.0	0.0
Other comprehensive (loss)			0.0	0.0	0.0	(164.1)
Stock-based compensation expense			115.5	0.0	0.0	0.0
Issuance relating to stock compensation plans			(15.8)	0.0	169.2	0.0
Treasury Stock, Acquired			0.0	0.0	(1,334.3)	0.0
Dividend received from CDK Global, Inc.	$ 0.0
Dividends, Stock			0.0	(1,008.5)	0.0	0.0
Common stock, shares issued, end of period at Jun. 30, 2017	638.7	638.7
Stockholders' Equity, balance, end of period at Jun. 30, 2017		$ 63.9	$ 867.8	$ 14,728.2	$ (11,303.7)	$ (379.2)