Financial Data By Segment Financial Data By Geographic Area Segment Table (Details) - USD ($) $ in Millions	3 Months Ended												12 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019		Mar. 31, 2019	[1]	Dec. 31, 2018	[1]	Sep. 30, 2018	[1]	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2018
Segment Reporting Information [Line Items]
TOTAL REVENUES	$ 3,376.8	$ 4,047.8	$ 3,669.5	$ 3,495.7	$ 3,479.3	[1]	$ 3,828.2		$ 3,492.4		$ 3,310.3		$ 14,589.8	$ 14,110.2	$ 13,274.2
Total assets	39,165.5				41,887.7								39,165.5	41,887.7	38,849.1
United States [Member]
Segment Reporting Information [Line Items]
TOTAL REVENUES													12,740.1	12,262.6	11,439.8
Total assets	33,891.0				36,508.3								33,891.0	36,508.3	33,586.6
Europe [Member]
Segment Reporting Information [Line Items]
TOTAL REVENUES													1,236.3	1,236.8	1,242.2
Total assets	2,162.7				2,807.9								2,162.7	2,807.9	2,608.6
CANADA [Member]
Segment Reporting Information [Line Items]
TOTAL REVENUES													329.8	326.6	321.6
Total assets	2,435.3				1,950.5								2,435.3	1,950.5	2,073.1
Other [Member]
Segment Reporting Information [Line Items]
TOTAL REVENUES													283.6	284.2	270.6
Total assets	$ 676.5				$ 621.0								$ 676.5	$ 621.0	$ 580.8

[1] (A) The prior period amounts presented have been revised to correct the amounts previously reported on a gross basis to a net basis by reducing PEO revenues and operating expenses for associated costs of an equal amount of $12.9 million, $13.5 million, $19.2 million and $19.4 million for the first quarter, second quarter, third quarter and fourth quarter, respectively. Refer to Note 1 to our consolidated financial statements for more information on this revision.