Earnings per Share (Detail) - shares	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Earnings Per Share [Abstract]
Weighted average number of shares for calculation of basic EPS	35,970,992	35,360,957	35,870,649	35,213,135
Stock options under the 2006, 2011 and 2013 equity plans	613,858	732,643	557,858	628,093
Weighted average number of shares for calculation of diluted EPS	36,584,850	36,093,600	36,428,507	35,841,228