Annual report pursuant to Section 13 and 15(d)

Equity - Summary of Unvested Shares of Restricted Common Stock (Detail)

v3.6.0.2
Equity - Summary of Unvested Shares of Restricted Common Stock (Detail) - Restricted Incentive [Member] - USD ($)
$ / shares in Units, $ in Millions
 12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Beginning Balance, Restricted Shares of Common Stock 1,248,069 964,820 598,815
Granted, Restricted Shares of Common Stock 661,055 586,648 529,100
Vested, Restricted Shares of Common Stock (716,264) (285,289) (149,709)
Forfeited, Restricted Shares of Common Stock (11,188) (18,110) (13,386)
Ending Balance, Restricted Shares of Common Stock 1,181,672 1,248,069 964,820
Beginning Balance, Weighted Average Share Price $ 15.16 $ 13.41 $ 12.50
Granted, Weighted Average Share Price 18.62 17.29 14.18
Vested, Weighted Average Share Price 14.03 13.61 12.50
Forfeited, Weighted Average Share Price 17.25 15.54 12.99
Ending Balance, Weighted Average Share Price $ 17.76 $ 15.16 $ 13.41
Beginning Balance, Fair Value of Restricted Shares of Common Stock $ 18.9 $ 12.9 $ 7.5
Granted, Fair Value of Restricted Shares of Common Stock 12.3 10.2 7.5
Vested, Fair Value of Restricted Shares of Common Stock (10.0) (3.9) (1.9)
Forfeited, Fair Value of Restricted Shares of Common Stock (0.2) (0.3) (0.2)
Ending Balance, Fair Value of Restricted Shares of Common Stock $ 21.0 $ 18.9 $ 12.9