Reclassifications out of Accumulated Other Comprehensive Income ("AOCI") (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2018	Mar. 31, 2017
AOCI Net of Tax [Roll Forward]
Accumulated other comprehensive income, beginning balance	$ (432.6)	$ (566.7)	$ (379.2)	$ (215.1)
Other comprehensive (loss)/income before reclassification adjustments	(219.3)	66.6	(332.9)	(462.2)
Tax effect	53.4	(16.5)	109.9	155.1
Reclassification adjustments to net earnings	2.5	5.3	8.2	14.2
Tax effect	(0.5)	(1.9)	(2.5)	(5.2)
Accumulated other comprehensive income, ending balance	(638.8)	(513.2)	(638.8)	(513.2)
Tax Cuts and Jobs Act of 2017, Reclassification from AOCI to Retained Earnings, Tax Effect	42.3		(42.3)
Currency Translation Adjustment
AOCI Net of Tax [Roll Forward]
Accumulated other comprehensive income, beginning balance	(184.2)	(298.0)	(230.8)	(253.8)
Other comprehensive (loss)/income before reclassification adjustments	21.1	20.3	67.7	(23.9)
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
Accumulated other comprehensive income, ending balance	(163.1)	(277.7)	(163.1)	(277.7)
Tax Cuts and Jobs Act of 2017, Reclassification from AOCI to Retained Earnings, Tax Effect	0.0		0.0
Net Gains/Losses on Available-for-sale Securities
AOCI Net of Tax [Roll Forward]
Accumulated other comprehensive income, beginning balance	(34.6)	19.9	68.3	333.8
Other comprehensive (loss)/income before reclassification adjustments	(240.4)	46.3	(400.6)	(438.3)
Tax effect	53.4	(16.5)	109.9	155.1
Reclassification adjustments to net earnings	0.2	0.2	1.3	(1.1)
Tax effect	0.1	(0.1)	(0.2)	0.3
Accumulated other comprehensive income, ending balance	(228.4)	49.8	(228.4)	49.8
Tax Cuts and Jobs Act of 2017, Reclassification from AOCI to Retained Earnings, Tax Effect	7.1		7.1
Pension Liability
AOCI Net of Tax [Roll Forward]
Accumulated other comprehensive income, beginning balance	(213.8)	(288.6)	(216.7)	(295.1)
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	2.3	5.1	6.9	15.3
Tax effect	(0.6)	(1.8)	(2.3)	(5.5)
Accumulated other comprehensive income, ending balance	(247.3)	$ (285.3)	(247.3)	$ (285.3)
Tax Cuts and Jobs Act of 2017, Reclassification from AOCI to Retained Earnings, Tax Effect	$ 35.2		$ 35.2

Reclassification From Accumulated Other Comprehensive Income, Current Period, Tax

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Tax Cuts and Jobs Act of 2017, Reclassification from AOCI to Retained Earnings, Tax Effect

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
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Amount before tax and reclassification adjustments of other comprehensive income (loss).

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Amount of tax expense (benefit) allocated to other comprehensive income (loss) before reclassification adjustment from accumulated other comprehensive income (loss).

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-Publisher FASB
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Amount before tax of reclassification adjustments of other comprehensive income (loss).

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