Earnings per Share (Detail)	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Weighted average number of shares for calculation of basic EPS – Common Stock	32,658,000	29,568,000	33,698,000	27,023,000
Impact of stock options outstanding under the 1997, 2006 and 2011 Stock Option Plans	508,917	535,918	445,175	617,704
Weighted average number of shares – diluted	33,167,000	30,103,000	34,143,000	27,641,000
Common stock that have been excluded from the diluted shares calculation	502,953	2,721,085	502,953	2,721,085
Stock options outstanding under the 2006, 2011 and 2013 Stock Option Plans
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Common stock that have been excluded from the diluted shares calculation	58,000	84,000	58,000	84,000
Series C Convertible Preferred Stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Common stock that have been excluded from the diluted shares calculation	444,953	2,637,085	444,953	2,637,085