Annual report pursuant to Section 13 and 15(d)

Dividends (Parenthetical) (Detail)

v3.3.1.900
Dividends (Parenthetical) (Detail) - USD ($)
$ / shares in Units, $ in Thousands
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Dividend Declared [Line Items]      
Dividends related to outstanding restricted stock units $ 593 $ 530 $ 772
Effective Date of change in amount of quarterly dividend Aug. 15, 2013    
Revised quarterly dividend $ 0.25