Quarterly report pursuant to Section 13 or 15(d)

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

v3.4.0.3
Equity - Summary of Unvested Shares of Restricted Common Stock (Detail) - Restricted Incentive [Member] - USD ($)
$ / shares in Units, $ in Millions
3 Months Ended 12 Months Ended
Mar. 31, 2016
Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Beginning Balance, Restricted Shares of Common Stock 1,248,069 964,820
Granted, Restricted Shares of Common Stock 647,970 586,648
Vested, Restricted Shares of Common Stock (29,268) (285,289)
Forfeited, Restricted Shares of Common Stock   (18,110)
Ending Balance, Restricted Shares of Common Stock 1,866,771 1,248,069
Beginning Balance, Weighted Average Share Price $ 15.16 $ 13.41
Granted, Weighted Average Share Price 18.58 17.29
Vested, Weighted Average Share Price 14.23 13.61
Forfeited, Weighted Average Share Price   15.54
Ending Balance, Weighted Average Share Price $ 16.36 $ 15.16
Beginning Balance, Fair Value of Restricted Shares of Common Stock $ 18.9 $ 12.9
Granted, Fair Value of Restricted Shares of Common Stock 12.0 10.2
Vested, Fair Value of Restricted Shares of Common Stock (0.4) (3.9)
Forfeited, Fair Value of Restricted Shares of Common Stock   (0.3)
Ending Balance, Fair Value of Restricted Shares of Common Stock $ 30.5 $ 18.9