Quarterly report pursuant to Section 13 or 15(d)

Long-Term Debt - Additional Information (Detail)

v3.8.0.1
Long-Term Debt - Additional Information (Detail)
1 Months Ended 3 Months Ended 9 Months Ended
Jun. 30, 2017
USD ($)
Sep. 30, 2015
USD ($)
May 04, 2015
USD ($)
Feb. 15, 2017
USD ($)
Feb. 28, 2014
USD ($)
$ / shares
Sep. 30, 2017
USD ($)
$ / shares
Jun. 30, 2017
USD ($)
Mar. 31, 2017
USD ($)
Sep. 30, 2016
USD ($)
$ / shares
Mar. 31, 2016
USD ($)
Mar. 31, 2014
USD ($)
Sep. 30, 2017
USD ($)
d
$ / shares
Sep. 30, 2016
USD ($)
$ / shares
Dec. 31, 2016
USD ($)
Jul. 26, 2012
USD ($)
Mar. 09, 2011
USD ($)
Debt Instrument [Line Items]                                
Deferred financing costs     $ 6,200,000                          
Interest expense           $ 43,000,000     $ 24,000,000     $ 117,400,000 $ 74,600,000      
Paid-in-capital in excess of par value           452,000,000           452,000,000   $ 467,600,000    
Long-term debt           2,280,700,000           2,280,700,000   1,447,900,000    
Convertible senior notes, carrying value of liability component           1,058,400,000           1,058,400,000   1,024,800,000    
Letters of credit issued but undrawn           37,900,000           37,900,000        
Prepaid forward share repurchase transactions [Member]                                
Debt Instrument [Line Items]                                
Paid-in-capital in excess of par value                     $ 31,900,000          
Forward share repurchase transactions amount         $ 685,800,000           685,800,000          
Capped call transactions [Member]                                
Debt Instrument [Line Items]                                
Capped call transactions with financial institutions         123,800,000                      
Senior secured prior revolving credit facility [Member]                                
Debt Instrument [Line Items]                                
Credit facility, amount repaid           0   $ 410,000,000                
Senior secured revolving credit facility [Member]                                
Debt Instrument [Line Items]                                
Borrowings under the senior secured credit facility           0           0        
Term Loan [Member]                                
Debt Instrument [Line Items]                                
Quarterly periodic payment, Principal $ 24,400,000                              
Interest expense           23,900,000           58,500,000        
Non-cash interest expense           1,200,000           3,000,000        
Amortization of deferred financing costs           800,000           2,000,000        
Term Loan [Member] | Level 2 [Member]                                
Debt Instrument [Line Items]                                
Carrying amount of Term Loan           1,212,600,000           1,212,600,000        
Debt instrument, fair value           1,228,000,000           1,228,000,000        
Convertible Debt [Member]                                
Debt Instrument [Line Items]                                
Deferred financing costs                     26,600,000          
Interest expense           17,200,000     16,400,000     50,900,000 48,700,000      
Non-cash interest expense           10,400,000     9,700,000     30,600,000 28,700,000      
Amortization of deferred financing costs           1,000,000     $ 900,000     3,000,000 $ 2,800,000      
Carrying amount of Term Loan         1,150,000,000 $ 1,150,000,000           $ 1,150,000,000   1,150,000,000    
Aggregate principal amount of convertible senior notes issued         1,000,000,000                      
Additional principal amount of convertible notes         $ 150,000,000                      
Convertible notes, interest rate         2.00%                      
Convertible notes maturity         Aug. 15, 2019                      
Convertible notes, conversion feature                       Holders of the Convertible Notes may convert their notes at their option under the following circumstances: (i) during any calendar quarter commencing after the calendar quarter ending March 31, 2014, if the last reported sale price of the Company’s common shares for at least 20 trading days (whether or not consecutive) in a period of 30 consecutive trading days ending on, and including, the last trading day of the immediately preceding calendar quarter exceeds 130% of the conversion price for the Convertible Notes on each applicable trading day; (ii) during the five business-day period immediately after any five consecutive trading day period, or the measurement period, in which the trading price per $1,000 principal amount of Convertible Notes for each trading day of that measurement period was less than 98% of the product of the last reported sale price of the Company’s common shares and the conversion rate for the Convertible Notes for each such day; or (iii) upon the occurrence of specified corporate events. On and after May 15, 2019, holders may convert their Convertible Notes at any time, regardless of the foregoing circumstances.        
Convertible notes, number of trading days of threshold limit (whether or not consecutive) | d                       20        
Convertible notes, number of trading days of threshold limit in consecutive days | d                       30        
Minimum percentage of common share price over conversion price for conversion         130.00%                      
Principal amount of convertible notes         $ 1,000                      
Minimum percentage of the product of common share price and conversion rate for convertible notes         98.00%                      
Convertible notes initial conversion rate         11.5908                      
Convertible notes initial conversion price | $ / shares           $ 86.28     $ 86.28     $ 86.28 $ 86.28      
Paid-in-capital in excess of par value         $ 219,100,000           5,100,000          
Proceeds received from the issuance of the Convertible notes         1,150,000,000                      
Long-term debt         $ 930,900,000                      
Effective interest rate on convertible notes         6.20%                      
Unamortized debt discount and debt issuance costs           $ 91,600,000           $ 91,600,000   125,200,000    
Convertible senior notes, carrying value of liability component           1,058,400,000           1,058,400,000   1,024,800,000    
Fair value of liability to convertible notes           $ 1,064,600,000           $ 1,064,600,000   $ 961,300,000    
Convertible Debt [Member] | Debt Issuance Costs [Member]                                
Debt Instrument [Line Items]                                
Deferred financing costs                     $ 21,500,000          
Convertible Debt [Member] | Capped call transactions [Member]                                
Debt Instrument [Line Items]                                
Convertible notes initial conversion price | $ / shares         $ 86.28                      
Senior Secured Credit Facility [Member]                                
Debt Instrument [Line Items]                                
Credit facility, maximum amount       $ 1,450,000,000                        
Credit facility amendment date                       May 04, 2015        
Credit facility interest rate description                       After March 9, 2016, the applicable interest rates on the Company’s borrowings under the Prior Credit Facility increased by 2.00% such that borrowings under the Prior Credit Facility began bearing interest at either LIBOR plus the applicable margin between 4.00% and 5.00% or the base rate plus the applicable margin between 3.00% and 4.00%        
Deferred financing costs       $ 22,600,000                        
Senior secured credit facility, discount percentage       2.00%                        
Senior secured credit facility, discount amount       $ 26,000,000                        
Repayment of prior senior secured credit facility       $ 410,000,000                        
Line of credit facility, frequency of interest payments       quarterly                        
Amount required to maintain on consolidated cash and cash equivalents                       $ 200,000,000        
Long-term debt, weighted average interest rate           6.71%           6.71%   4.29%    
Annual scheduled principal payments of debt, Remainder of 2017           $ 26,200,000           $ 26,200,000        
Annual scheduled principal payments of debt, 2018           102,300,000           102,300,000        
Annual scheduled principal payments of debt, 2019           1,250,000,000           1,250,000,000        
Annual scheduled principal payments of debt, 2020           97,900,000           97,900,000        
Annual scheduled principal payments of debt, 2021           97,500,000           97,500,000        
Annual scheduled principal payments of debt, 2022           97,500,000           97,500,000        
Annual scheduled principal payments of debt, 2023           739,400,000           $ 739,400,000        
Senior Secured Credit Facility [Member] | Senior secured prior revolving credit facility [Member]                                
Debt Instrument [Line Items]                                
Line of credit facility extended maturity period                       1 year        
Credit facility prepayments     50,900,000                          
Credit facility, maximum amount                           $ 425,000,000   $ 700,000,000
Amended maturity date of credit facility                       Mar. 09, 2017        
Decreased amount in credit facility borrowing capacity   $ (39,100,000) (235,900,000)                          
Borrowings under the senior secured credit facility                           410,000,000    
Foreign currency borrowings, outstanding           0           $ 0   $ 0    
Senior Secured Credit Facility [Member] | Senior secured revolving credit facility [Member]                                
Debt Instrument [Line Items]                                
Credit facility, maximum amount       $ 150,000,000                        
Credit facility, maturity date                       Feb. 15, 2022        
Credit facility LIBOR minimum floor rate interest       0.75%                        
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage       0.50%                        
Senior Secured Credit Facility [Member] | Prior Term Loan [Member]                                
Debt Instrument [Line Items]                                
Credit facility prepayments     $ 20,300,000                          
Credit facility, maximum amount                             $ 500,000,000  
Credit facility, amount repaid                   $ 229,700,000            
Senior Secured Credit Facility [Member] | Term Loan [Member]                                
Debt Instrument [Line Items]                                
Credit facility, maximum amount       $ 1,300,000,000                        
Credit facility, maturity date                       Feb. 15, 2023        
Credit facility, amount repaid           24,400,000 $ 24,400,000                  
Borrowings under the senior secured credit facility           $ 1,251,200,000           $ 1,251,200,000        
Senior Secured Credit Facility [Member] | LIBOR [Member]                                
Debt Instrument [Line Items]                                
Interest rate spread on variable rate       1.00%                        
Senior Secured Credit Facility [Member] | LIBOR [Member] | Senior secured prior revolving credit facility [Member]                                
Debt Instrument [Line Items]                                
Credit facility LIBOR minimum floor rate interest     0.25%                          
Senior Secured Credit Facility [Member] | Base Rate [Member]                                
Debt Instrument [Line Items]                                
Variable rate basis                       Facility increased by 2.00% such that borrowings under the Prior Credit Facility began bearing interest at either LIBOR plus the applicable margin between 4.00% and 5.00% or the base rate plus the applicable margin between 3.00% and 4.00%        
Base rate interest rate floor       1.75%                        
Senior Secured Credit Facility [Member] | Base Rate [Member] | Term Loan [Member]                                
Debt Instrument [Line Items]                                
Interest rate spread on variable rate       4.50%                        
Senior Secured Credit Facility [Member] | Eurodollar [Member] | Term Loan [Member]                                
Debt Instrument [Line Items]                                
Interest rate spread on variable rate       5.50%                        
Senior Secured Credit Facility [Member] | Federal Funds Rate [Member]                                
Debt Instrument [Line Items]                                
Interest rate spread on variable rate       0.50%                        
Until March 9, 2016 [Member] | Senior Secured Credit Facility [Member]                                
Debt Instrument [Line Items]                                
Interest rate spread on variable rate increase by percentage     0.50%                          
After March 9, 2016 [Member] | Senior Secured Credit Facility [Member]                                
Debt Instrument [Line Items]                                
Interest rate increased by percentage     2.00%                          
After March 9, 2016 [Member] | Senior Secured Credit Facility [Member] | LIBOR [Member] | Minimum [Member]                                
Debt Instrument [Line Items]                                
Interest rate spread on variable rate     4.00%                          
After March 9, 2016 [Member] | Senior Secured Credit Facility [Member] | LIBOR [Member] | Maximum [Member]                                
Debt Instrument [Line Items]                                
Interest rate spread on variable rate     5.00%                          
After March 9, 2016 [Member] | Senior Secured Credit Facility [Member] | Base Rate [Member] | Minimum [Member]                                
Debt Instrument [Line Items]                                
Interest rate spread on variable rate     3.00%                          
After March 9, 2016 [Member] | Senior Secured Credit Facility [Member] | Base Rate [Member] | Maximum [Member]                                
Debt Instrument [Line Items]                                
Interest rate spread on variable rate     4.00%                          
Until August 15, 2017 [Member] | Senior Secured Credit Facility [Member] | Base Rate [Member] | Senior secured revolving credit facility [Member]                                
Debt Instrument [Line Items]                                
Interest rate spread on variable rate       3.75%                        
Until August 15, 2017 [Member] | Senior Secured Credit Facility [Member] | Eurodollar [Member] | Senior secured revolving credit facility [Member]                                
Debt Instrument [Line Items]                                
Interest rate spread on variable rate       4.75%                        
Scenario Leverage Ratio One [Member] | Senior Secured Credit Facility [Member] | Base Rate [Member] | Senior secured revolving credit facility [Member] | After August 15, 2017 [Member]                                
Debt Instrument [Line Items]                                
Interest rate spread on variable rate       3.50%                        
Scenario Leverage Ratio One [Member] | Senior Secured Credit Facility [Member] | Eurodollar [Member] | Senior secured revolving credit facility [Member] | After August 15, 2017 [Member]                                
Debt Instrument [Line Items]                                
Interest rate spread on variable rate       4.50%                        
Scenario Leverage Ratio Two [Member] | Senior Secured Credit Facility [Member] | Base Rate [Member] | Senior secured revolving credit facility [Member] | After August 15, 2017 [Member]                                
Debt Instrument [Line Items]                                
Interest rate spread on variable rate       3.75%                        
Scenario Leverage Ratio Two [Member] | Senior Secured Credit Facility [Member] | Eurodollar [Member] | Senior secured revolving credit facility [Member] | After August 15, 2017 [Member]                                
Debt Instrument [Line Items]                                
Interest rate spread on variable rate       4.75%