Reclassifications out of Accumulated Other Comprehensive Income (AOCI) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
AOCI Net of Tax [Roll Forward]
Beginning balance	$ 5,808.9	$ 5,360.7	$ 5,752.2	$ 5,399.9
Other comprehensive (loss)/income before reclassification adjustments	17.8	(0.5)	40.3	46.7
Tax effect	10.0	7.3	16.3	(13.5)
Reclassification adjustments to net earnings	(4.1)	(5.2)	(1.3)	(9.2)
Tax effect	0.7	1.1	(0.2)	2.1
Ending balance	5,900.0	5,364.4	5,900.0	5,364.4
AOCI
AOCI Net of Tax [Roll Forward]
Beginning balance	15.9	(233.9)	(14.8)	(257.3)
Ending balance	40.3	(231.2)	40.3	(231.2)
Currency Translation Adjustment
AOCI Net of Tax [Roll Forward]
Beginning balance	(271.8)	(318.1)	(322.2)	(269.2)
Other comprehensive (loss)/income before reclassification adjustments	61.9	34.3	112.3	(14.6)
Tax effect	0.0	0.0	0.0	0.0
Reclassification adjustments to net earnings	0.0	0.0	0.0	0.0
Tax effect	0.0	0.0	0.0	0.0
Ending balance	(209.9)	(283.8)	(209.9)	(283.8)
Net Gains/Losses on Available-for-sale Securities
AOCI Net of Tax [Roll Forward]
Beginning balance	661.1	298.1	680.4	224.6
Other comprehensive (loss)/income before reclassification adjustments	(44.1)	(35.5)	(68.7)	60.6
Tax effect	10.0	7.5	15.5	(13.3)
Reclassification adjustments to net earnings	(7.7)	(7.1)	(8.0)	(9.4)
Tax effect	1.7	1.6	1.8	2.1
Ending balance	621.0	264.6	621.0	264.6
Cash Flow Hedging Activities
AOCI Net of Tax [Roll Forward]
Beginning balance	(32.2)	0.0	(30.3)	0.0
Other comprehensive (loss)/income before reclassification adjustments	0.0	0.7	(3.3)	0.7
Tax effect	0.0	(0.2)	0.8	(0.2)
Reclassification adjustments to net earnings	1.1	0.0	1.7	0.0
Tax effect	(0.4)	0.0	(0.4)	0.0
Ending balance	(31.5)	0.5	(31.5)	0.5
Pension Liability
AOCI Net of Tax [Roll Forward]
Beginning balance	(341.2)	(213.9)	(342.7)	(212.7)
Other comprehensive (loss)/income before reclassification adjustments	0.0	0.0	0.0	0.0
Tax effect	0.0	0.0	0.0	0.0
Reclassification adjustments to net earnings	2.5	1.9	5.0	0.2
Tax effect	(0.6)	(0.5)	(1.6)	0.0
Ending balance	$ (339.3)	$ (212.5)	$ (339.3)	$ (212.5)

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Amount before tax and reclassification adjustments of other comprehensive income (loss) attributable to parent.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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