Quarterly report pursuant to Section 13 or 15(d)

Equity-Based Compensation (Restricted Stock and RSUs to be Settled in Common Stock) - Additional Information (Detail)

v3.7.0.1
Equity-Based Compensation (Restricted Stock and RSUs to be Settled in Common Stock) - Additional Information (Detail) - USD ($)
$ / shares in Units, $ in Thousands, shares in Millions
3 Months Ended
Mar. 31, 2017
Mar. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Non-cash stock compensation expense $ 11,866 $ 13,719
Restricted Stock and Restricted Stock Units to be Settled in Common Stock [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Awards vested 1.3 1.2
Fair value of restricted stock, vested $ 50,500 $ 25,300
Non-cash stock compensation expense $ 11,200 $ 13,200
Restricted Stock and Restricted Stock Units to be Settled in Common Stock [Member] | Maximum [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Vesting period for restricted stock and restricted stock units 3 years  
Restricted Stock and Restricted Stock Units to be Settled in Common Stock [Member] | Minimum [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Vesting period for restricted stock and restricted stock units 2 years  
Restricted Stock Units to be Settled in Common Stock [Member]    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Granted, shares 1.1 1.7
Granted, weighted average grant date fair value, per share $ 38.18 $ 21.95
Unrecognized compensation cost, related to unvested restricted stock, total $ 54,000  
Expected weighted average period to recognize compensation cost on restricted stock and RSUs to be settled in stock (in years) 2 years 29 days