Computation of Earnings Per Share (Parenthetical) (Detail) - shares		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Earnings Per Share Basic And Diluted [Line Items]
Potential dilutive effect of restricted stock considered antidilutive	[1]		167,000	186,000
Restricted Stock
Earnings Per Share Basic And Diluted [Line Items]
Potential dilutive effect of restricted stock considered antidilutive		103

[1] For calculating dilutive earning(loss) per share during the year ended December 31, 2016, potential dilutive effect of restricted stock of 103 units are not considered as they are antidilutive in view of current year loss.