Accumulated Other Comprehensive Loss - Schedule of Changes in the Components of AOCI (Details) - USD ($) $ in Millions	3 Months Ended
Jun. 30, 2021	Jun. 30, 2020
Changes in the components of AOCI
Beginning balance	$ 5,337.1	$ 5,585.5
Other comprehensive income, net of tax effect	0.0	0.5
Ending balance	5,519.9	5,501.3
Total
Changes in the components of AOCI
Beginning balance	(26.2)	(21.6)
Other comprehensive (loss) income before reclassifications	(0.6)
Reclassification of realized transactions	0.6
Other comprehensive income, net of tax effect	0.0	0.5
Ending balance	(26.2)	$ (21.1)
Minimum Pension Liability
Changes in the components of AOCI
Beginning balance	(13.4)
Other comprehensive (loss) income before reclassifications	(1.1)
Reclassification of realized transactions	0.6
Other comprehensive income, net of tax effect	(0.5)
Ending balance	(13.9)
Foreign Currency
Changes in the components of AOCI
Beginning balance	(12.8)
Other comprehensive (loss) income before reclassifications	0.5
Reclassification of realized transactions	0.0
Other comprehensive income, net of tax effect	0.5
Ending balance	$ (12.3)

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

No definition available.

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

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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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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