Other Comprehensive Income (Loss), Net of Tax, Including Cumulative Effect of Adoption

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- Definition

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

+ References

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.

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
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- Definition

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

+ References

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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
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Accumulated Other Comprehensive Income (Loss) - Changes in Accumulated Other Comprehensive Income (Loss) (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Jan. 01, 2018
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	$ 1,746.7	$ 1,819.7	$ 1,792.7
Other comprehensive (loss) income before reclassifications	72.2	(82.8)
Amounts reclassified from accumulated other comprehensive income	8.7	4.9
Net current-period other comprehensive (loss) income	80.9	(77.9)
Ending Balance	1,781.1	1,746.7	1,819.7
Accounting Standards Update 2016-01 [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Cumulative effect of adoption of ASU, net of taxes				$ 0.0
Accounting Standards Update 2018-02 [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Cumulative effect of adoption of ASU, net of taxes				0.0
Foreign Currency Translation Adjustments [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(22.4)	(19.0)
Other comprehensive (loss) income before reclassifications	(0.2)	(3.4)
Amounts reclassified from accumulated other comprehensive income	0.0	0.0
Net current-period other comprehensive (loss) income	(0.2)	(3.4)
Ending Balance	(22.6)	(22.4)	(19.0)
Foreign Currency Translation Adjustments [Member] \| Accounting Standards Update 2016-01 [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Cumulative effect of adoption of ASU, net of taxes				0.0
Foreign Currency Translation Adjustments [Member] \| Accounting Standards Update 2018-02 [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Cumulative effect of adoption of ASU, net of taxes				0.0
Unrealized Holding Gains on Securities [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(49.0)	121.9
Other comprehensive (loss) income before reclassifications	73.8	(80.4)
Amounts reclassified from accumulated other comprehensive income	8.7	4.9	(28.2)
Net current-period other comprehensive (loss) income	82.5	(75.5)
Ending Balance	33.5	(49.0)	121.9
Unrealized Holding Gains on Securities [Member] \| Accounting Standards Update 2016-01 [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Cumulative effect of adoption of ASU, net of taxes				(117.5)
Unrealized Holding Gains on Securities [Member] \| Accounting Standards Update 2018-02 [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Cumulative effect of adoption of ASU, net of taxes				22.1
Defined Benefit Pension Plans [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(6.7)	(6.3)
Other comprehensive (loss) income before reclassifications	(1.4)	1.0
Amounts reclassified from accumulated other comprehensive income	0.0	0.0
Net current-period other comprehensive (loss) income	(1.4)	1.0
Ending Balance	(8.1)	(6.7)	(6.3)
Defined Benefit Pension Plans [Member] \| Accounting Standards Update 2016-01 [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Cumulative effect of adoption of ASU, net of taxes				0.0
Defined Benefit Pension Plans [Member] \| Accounting Standards Update 2018-02 [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Cumulative effect of adoption of ASU, net of taxes				(1.4)
AOCI Attributable to Parent [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance	(78.1)	96.6	47.7
Ending Balance	$ 2.8	$ (78.1)	$ 96.6
AOCI Attributable to Parent [Member] \| Accounting Standards Update 2016-01 [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Cumulative effect of adoption of ASU, net of taxes				(117.5)
AOCI Attributable to Parent [Member] \| Accounting Standards Update 2018-02 [Member]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Cumulative effect of adoption of ASU, net of taxes				$ 20.7