Changes in Accumulated Other Comprehensive Income/(Loss) by Component - Reconciliation of Changes in Accumulated Other Comprehensive Income/(Loss) by Component (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Accumulated Other Comprehensive Income (Loss) by Component			$ (11.0)
Beginning balance	$ 1,944.3	$ 2,056.7	1,985.1	$ 1,996.7
Reclassification of interest rate swap to income, net of tax		2.2		6.9
Pension adjustments, net of tax		0.4		1.6
Amortization of actuarial gain (losses), net of tax	0.5	0.1	0.1	0.2
Foreign currency translation adjustments, net of tax	(69.0)	(22.3)	(173.4)	(45.7)
Net current-period other comprehensive income (loss)	(68.5)	(19.6)	(173.3)	(37.0)
Accumulated Other Comprehensive Income (Loss) by Component	(184.3)		(184.3)
Ending balance	1,905.5	2,068.4	1,905.5	2,068.4
Gains and (Losses) on Cash Flow Hedges [Member]
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Accumulated Other Comprehensive Income (Loss) by Component		(16.8)		(21.5)
Reclassification of interest rate swap to income, net of tax		2.2		6.9
Net current-period other comprehensive income (loss)		2.2		6.9
Accumulated Other Comprehensive Income (Loss) by Component		(14.6)		(14.6)
Pension & Other Post Retirement and Defined Benefit Pension Plans [Member]
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Accumulated Other Comprehensive Income (Loss) by Component	(0.2)	(2.4)	0.2	(3.7)
Pension adjustments, net of tax		0.4		1.6
Amortization of actuarial gain (losses), net of tax	0.5	0.1	0.1	0.2
Net current-period other comprehensive income (loss)	0.5	0.5	0.1	1.8
Accumulated Other Comprehensive Income (Loss) by Component	0.3	(1.9)	0.3	(1.9)
Cumulative Foreign Currency Translation Adjustment [Member]
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Accumulated Other Comprehensive Income (Loss) by Component	(115.6)	22.9	(11.2)	46.3
Foreign currency translation adjustments, net of tax	(69.0)	(22.3)	(173.4)	(45.7)
Net current-period other comprehensive income (loss)	(69.0)	(22.3)	(173.4)	(45.7)
Accumulated Other Comprehensive Income (Loss) by Component	(184.6)	0.6	(184.6)	0.6
Accumulated Other Comprehensive Income (Loss) [Member]
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(115.8)	3.7	(11.0)	21.1
Ending balance	$ (184.3)	$ (15.9)	$ (184.3)	$ (15.9)

Other comprehensive income (loss) amortization of actuarial gain (losses), net of tax.

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- Definition

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.

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

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- Definition

Amount, after tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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- Definition

Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount, after tax, before reclassification adjustment, of (increase) decrease in accumulated other comprehensive income of defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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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.

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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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