Annual report pursuant to Section 13 and 15(d)

Segment Information - Schedule of Entity-Wide Information, Revenue from External Customers by Products and Services (Detail)

v3.19.3.a.u2
Segment Information - Schedule of Entity-Wide Information, Revenue from External Customers by Products and Services (Detail) - USD ($)
$ in Millions
 3 Months Ended 12 Months Ended
Dec. 31, 2019
 [1]
Sep. 30, 2019
Jun. 30, 2019
Mar. 31, 2019
Dec. 31, 2018
 [1]
Sep. 30, 2018
Jun. 30, 2018
Mar. 31, 2018
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Revenue from External Customer [Line Items]                      
Total net sales $ 1,220.3 $ 1,244.5 $ 1,240.1 $ 1,172.2 $ 1,186.6 $ 1,242.8 $ 1,285.5 $ 1,176.9 $ 4,877.1 $ 4,891.8 $ 4,427.7
Weight Management [Member]                      
Revenue from External Customer [Line Items]                      
Total net sales                 3,012.5 3,105.8 2,842.5
Targeted Nutrition [Member]                      
Revenue from External Customer [Line Items]                      
Total net sales                 1,278.5 1,243.5 1,082.8
Outer Nutrition [Member]                      
Revenue from External Customer [Line Items]                      
Total net sales                 97.3 91.9 93.9
Literature, Promotional and Other [Member]                      
Revenue from External Customer [Line Items]                      
Total net sales                 136.8 142.2 144.7
Energy, Sports, and Fitness [Member]                      
Revenue from External Customer [Line Items]                      
Total net sales                 $ 352.0 $ 308.4 $ 263.8
[1] The fourth quarter of 2019 includes a net favorable adjustment to our unrecognized tax benefit liability of $11.4 million primarily attributable to transfer pricing matters in various foreign jurisdictions, and a legal accrual of $40 million relating to the SEC and DOJ investigations relating to the FCPA matter in China as described further in Note 7, Contingencies. The fourth quarter of 2018 includes an unfavorable impact of U.S. Tax Reform enacted during the fourth quarter of 2017, as described further in Note 12, Income Taxes.