Quarterly report pursuant to Section 13 or 15(d)

Shareholders' Equity (Deficit) - Additional Information (Detail)

v3.5.0.2
Shareholders' Equity (Deficit) - Additional Information (Detail) - USD ($)
$ / shares in Units, $ in Millions
1 Months Ended 3 Months Ended 9 Months Ended
Feb. 28, 2014
Sep. 30, 2016
Sep. 30, 2015
Mar. 31, 2014
Sep. 30, 2016
Sep. 30, 2015
Dec. 31, 2015
Feb. 03, 2014
Jul. 30, 2012
Stockholders Equity [Line Items]                  
Share repurchase program authorized amount               $ 1,500.0 $ 1,000.0
Share repurchase program expiration date         Jun. 30, 2017        
Accumulated deficit   $ (165.7)     $ (165.7)   $ (326.3)    
Paid-in-capital in excess of par value   462.6     462.6   $ 438.2    
Non-cash forward transaction issuance costs       $ 35.8          
Non-cash interest expense relating to amortization of non-cash issuance costs   1.6 $ 1.6   4.8 $ 4.8      
Other comprehensive income (loss) before foreign currency translation adjustments reclassifications, Tax expense (benefits)   5.8 (2.7)   7.3 (7.0)      
Other comprehensive Unrealized Gain (Loss) on Derivatives before reclassifications, Tax expense (benefits)     (0.3)   (0.3) 0.2      
Amounts reclassified from accumulated other comprehensive income (loss) to income, Tax expense (benefits)         $ 0.1 0.8      
Other comprehensive Unrealized Gain (Loss) on Available-For-Sale Investments before reclassifications, Tax expense (benefits)           (1.0)      
Unrealized Gain (Loss) on Derivatives [Member]                  
Stockholders Equity [Line Items]                  
Amounts reclassified from accumulated other comprehensive income (loss) to income, tax expense (benefits) unrealized gain (loss) on derivatives     $ 0.1     $ (0.1)      
Capped call transactions [Member]                  
Stockholders Equity [Line Items]                  
Capped call transactions with financial institutions $ 123.8                
Capped call transactions price per common share $ 120.79                
Increase (decrease) in additional paid-in capital, other       (123.8)          
Capped call transactions [Member] | Convertible Notes [Member]                  
Stockholders Equity [Line Items]                  
Convertible notes initial conversion price $ 86.28                
Prepaid forward share repurchase transactions [Member]                  
Stockholders Equity [Line Items]                  
Forward share repurchase transactions amount $ 685.8     685.8          
Share repurchase transaction, shares to be purchased 9,900,000                
Average cost per share of shares repurchased $ 69.02                
Settlement date of forward transactions         Aug. 15, 2019        
Accumulated deficit       (653.9)          
Paid-in-capital in excess of par value       $ 31.9          
Share repurchase program, remaining authorized capacity   $ 232.9     $ 232.9        
Open market purchases [Member]                  
Stockholders Equity [Line Items]                  
Repurchase of common stock, shares   0 0   0 0