Quarterly report pursuant to Section 13 or 15(d)

Significant Accounting Policies - Additional Information (Detail)

v3.10.0.1
Significant Accounting Policies - Additional Information (Detail)
$ in Millions
 1 Months Ended 3 Months Ended 6 Months Ended 12 Months Ended
May 14, 2018
shares
Apr. 24, 2018
Mar. 31, 2018
USD ($)
Feb. 28, 2014
Jun. 30, 2018
USD ($)
Jun. 30, 2017
USD ($)
Jun. 30, 2018
USD ($)
Segment
Product
Jun. 30, 2017
USD ($)
Dec. 31, 2017
USD ($)
Jan. 01, 2018
USD ($)
Subsidiary or Equity Method Investee [Line Items]                    
Stock split description   On April 24, 2018, the Company’s shareholders approved a two-for-one stock split of the Company’s common shares. On May 14, 2018, shareholders of record received one additional share for each share held as of May 7, 2018.                
Stock split conversion ratio   2   2            
Additional number of share received for each share held by shareholders | shares 1                  
Credit card receivables         $ 82.3   $ 82.3   $ 68.1  
Bad-debt expense         0.4 $ 0.2 0.5 $ 0.4    
Allowance for doubtful accounts         1.3   1.3   1.2  
Allowances for product returns             $ 4.8   $ 3.9  
Number of geographic regions | Segment             6      
Number of product categories | Product             5      
Other operating income         1.7 38.9 $ 17.9 38.9    
Other expense, net         (4.7) 0.0 (29.1) 0.0    
October 2017 Dutch Auction Tender Offer [Member]                    
Subsidiary or Equity Method Investee [Line Items]                    
Loss recognized in other expense         4.7   16.0      
Convertible Senior Notes Due 2019 [Member]                    
Subsidiary or Equity Method Investee [Line Items]                    
Stock split conversion ratio   2                
Convertible Senior Notes Due 2019 [Member] | Repurchase of 2019 Convertible Notes [Member]                    
Subsidiary or Equity Method Investee [Line Items]                    
Loss on extinguishment of debt     $ 13.1       13.1      
Repurchase of convertible notes     $ 475.0       475.0      
China [Member]                    
Subsidiary or Equity Method Investee [Line Items]                    
Other operating income         1.7 $ 38.9 17.9 $ 38.9    
Accounting Standards Update 2014-09 [Member]                    
Subsidiary or Equity Method Investee [Line Items]                    
Net reduction of retained earnings due to cumulative impact                   $ 2.3
Other operating income         1.7   17.9      
Other expense, net         $ (4.7)   $ (29.1)