Quarterly report pursuant to Section 13 or 15(d)

Summary of Restricted Stock Activity (Detail)

v3.7.0.1
Summary of Restricted Stock Activity (Detail) - Restricted Stock
3 Months Ended
Mar. 31, 2017
$ / shares
shares
Shares of Restricted Stock  
Shares of Restricted Stock, Beginning balance | shares 606,618
Shares of Restricted Stock, Granted | shares 178,259
Shares of Restricted Stock, Vested | shares (137,992)
Shares of Restricted Stock, Forfeited | shares (855)
Shares of Restricted Stock, Ending balance | shares 646,030
Shares of Restricted Stock, Unvested restricted stock | shares 646,030
Weighted Average Grant Date Fair Value  
Weighted Average Grant Date Fair Value Outstanding, Beginning | $ / shares $ 33.51
Weighted Average Grant Date Fair Value, Granted | $ / shares 42.37
Weighted Average Grant Date Fair Value, Vested | $ / shares 36.18
Weighted Average Grant Date Fair Value, Forfeited | $ / shares 36.55
Weighted Average Grant Date Fair Value Outstanding, Ending | $ / shares 35.38
Weighted Average Grant Date Fair Value, Unvested restricted stock | $ / shares $ 35.38