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Employee Benefit Plans (Narrative) (Details) - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Nov. 12, 2019	Aug. 28, 2015
Defined Benefit Plan Disclosure [Line Items]
Stock repurchase program, authorized amount					$ 5,000.0
Stock repurchase program, shares authorized (in shares)						25.0
Treasury stock acquired (shares)	1.8	2.2	3.7	3.8
Treasury stock acquired, value	$ 311.5	$ 312.3	$ 704.0	$ 594.1
Defined benefit plan, benefit obligation, payment for settlement	0.0	$ (12.8)	$ 5.1	$ (28.1)
November 2019 Authorization
Defined Benefit Plan Disclosure [Line Items]
Treasury stock acquired, value	$ 155.4