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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- Definition

Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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No definition available.

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- Definition

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

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- Definition

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

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

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- Definition

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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Amount of stockholders' equity including the portion attributable to noncontrolling interests, after the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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Accumulated Other Comprehensive Loss - Schedule of Changes in the Components of AOCI (Details) - USD ($) $ in Millions	3 Months Ended						9 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2019	Dec. 31, 2018	Apr. 01, 2019
Changes in the components of AOCI
Beginning balance	$ 5,361.3	$ 5,288.3	$ 5,287.5	$ 5,170.2	$ 5,123.8	$ 3,279.8	$ 5,287.5	$ 3,279.8
Impact of change in accounting principle									$ 0.0
Other comprehensive income (loss), net of tax effect	0.3	0.0	(0.3)	(0.3)	(1.8)	4.4	0.0	2.3
Ending balance	5,616.6	5,361.3	5,288.3	5,161.1	5,170.2	5,123.8	5,616.6	5,161.1
AOCI Attributable to Parent
Changes in the components of AOCI
Beginning balance	(22.3)	(22.3)	(20.7)	(16.7)	(14.9)	(17.6)	(20.7)	(17.6)
Impact of change in accounting principle									(1.3)
Opening balance									(22.0)
Other comprehensive income (loss) before reclassifications							(0.6)
Amounts reclassified from accumulated other comprehensive income (loss)							0.6
Other comprehensive income (loss), net of tax effect	0.3		(0.3)	(0.3)	(1.8)	4.4	0.0
Ending balance	(22.0)	$ (22.3)	(22.3)	$ (17.0)	$ (16.7)	$ (14.9)	(22.0)	$ (17.0)
Unrealized holding gains (losses) available-for-sale debt securities
Changes in the components of AOCI
Beginning balance			0.2				0.2
Impact of change in accounting principle									(0.2)
Opening balance									0.0
Other comprehensive income (loss) before reclassifications							0.0
Amounts reclassified from accumulated other comprehensive income (loss)							0.0
Other comprehensive income (loss), net of tax effect							0.0
Ending balance	0.0						0.0
Defined benefit pension plans
Changes in the components of AOCI
Beginning balance			(6.2)				(6.2)
Impact of change in accounting principle									(1.1)
Opening balance									(7.3)
Other comprehensive income (loss) before reclassifications							0.1
Amounts reclassified from accumulated other comprehensive income (loss)							0.6
Other comprehensive income (loss), net of tax effect							0.7
Ending balance	(6.6)						(6.6)
Foreign Currency
Changes in the components of AOCI
Beginning balance			$ (14.7)				(14.7)
Impact of change in accounting principle									0.0
Opening balance									$ (14.7)
Other comprehensive income (loss) before reclassifications							(0.7)
Amounts reclassified from accumulated other comprehensive income (loss)							0.0
Other comprehensive income (loss), net of tax effect							(0.7)
Ending balance	$ (15.4)						$ (15.4)