Segment Information - Reconciliation of Operating Profit (Loss) from Segments to Consolidated (Detail) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Contribution Margin
Total Contribution Margin		$ 582.7	$ 624.0	$ 1,120.2	$ 1,218.9
Selling, general and administrative expenses	[1]	460.5	470.0	936.4	924.9
Other operating income		(1.2)	(1.8)	(10.1)	(14.9)
Interest expense, net		38.4	31.7	77.8	61.4
Income before income taxes		85.0	124.1	116.1	247.5
Income taxes		25.1	37.6	26.9	62.8
Net income		59.9	86.5	89.2	184.7
Primary Reporting Segment [Member]
Contribution Margin
Total Contribution Margin		507.6	534.1	990.1	1,038.5
China [Member]
Contribution Margin
Total Contribution Margin		75.1	89.9	130.1	180.4
Other operating income		$ (1.2)	$ (1.8)	$ (10.1)	$ (14.9)

[1] Contribution margin consists of net sales less cost of sales and Royalty overrides. For the China segment, contribution margin does not include the portion of service fees to China independent service providers included in selling, general, and administrative expenses, which totaled $44.5 million and $52.2 million for the three months ended June 30, 2023 and 2022, respectively, and $78.2 million and $106.4 million for the six months ended June 30, 2023 and 2022, respectively.