Accumulated Other Comprehensive Loss - Details of Comprehensive Income (Loss) (Detail) - USD ($) $ in Millions		3 Months Ended		12 Months Ended
	Oct. 01, 2018	Dec. 31, 2018		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period				$ 348.6
Other comprehensive (loss) income before reclassifications				8.9	$ (64.0)
Less: amounts reclassified from accumulated other comprehensive loss				2.5	1.9	$ 7.8
Other comprehensive income (loss)				11.4	(62.1)	104.2
Balance at end of period		$ 348.6		196.2	348.6
Intra-entity foreign currency translation adjustment		(744.8)		(728.6)	(744.8)
Unrecognized Pension Items
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period				136.4	103.4
Other comprehensive (loss) income before reclassifications				(13.3)	(31.5)
Less: amounts reclassified from accumulated other comprehensive loss				3.6	2.1
Other comprehensive income (loss)				(9.7)	(29.4)
Impact of Accounting Standard Update					(3.6)
Balance at end of period		136.4		146.1	136.4	103.4
Cumulative Translation Adjustment
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period				744.8	694.4
Other comprehensive (loss) income before reclassifications				16.2	(50.4)
Less: amounts reclassified from accumulated other comprehensive loss				0.0	0.0
Other comprehensive income (loss)				16.2	(50.4)
Impact of Accounting Standard Update					0.0
Balance at end of period		744.8		728.6	744.8	694.4
Cumulative Translation Adjustment | Intra-entity transactions
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Intra-entity foreign currency translation adjustment		65.8		(4.5)	65.8	(78.2)
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent | Net Investment Hedge
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period				41.9	46.8
Other comprehensive (loss) income before reclassifications				7.4	15.0
Less: amounts reclassified from accumulated other comprehensive loss				0.0	0.0
Other comprehensive income (loss)				7.4	15.0
Impact of Accounting Standard Update					(10.1)
Balance at end of period		41.9		34.5	41.9	46.8
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent | Cash Flow Hedge
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period				(2.7)	0.3
Other comprehensive (loss) income before reclassifications				(1.4)	2.9
Less: amounts reclassified from accumulated other comprehensive loss				(1.1)	(0.2)
Other comprehensive income (loss)				(2.5)	2.7
Impact of Accounting Standard Update					0.3
Balance at end of period		(2.7)		(0.2)	(2.7)	0.3
Accumulated Other Comprehensive Loss, Net of Taxes
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period				920.4	844.9
Impact of Accounting Standard Update					(13.4)
Balance at end of period		920.4		$ 909.0	$ 920.4	$ 844.9
ASU 2018-02
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Impact of Accounting Standard Update	$ (13.4)	$ 13.4	[1]

[1] Due to the adoption of ASU 2016-16, Income Taxes (Topic 740): Intra-Entity Transfers of Assets Other Than Inventory and ASU 2014-09, Revenue from Contracts with Customers (Topic 606) as of January 1, 2018, the Company recorded decreases to retained earnings of $1.0 million and $2.4 million, respectively. Additionally, due to the adoption of ASU 2018-02, Income Statement - Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income as of October 1, 2018, the Company recorded an increase to retained earnings of $13.4 million from accumulated other comprehensive loss.