Earnings per Share (Detail)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Weighted average number of shares for calculation of basic EPS - Common Stock	28,352,864	22,605,518	21,716,775
Stock options under Plans	509,599	849,104	779,472
Weighted average number of shares for calculation of diluted EPS - Common Stock	28,862,463	23,454,622	22,496,247
Common stock that have been excluded from the diluted shares calculation	1,680,891	3,798,518	155,826
Stock options outstanding under the 1993,1997, 2006 and 2011 Stock Option Plans [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Common stock that have been excluded from the diluted shares calculation	149,000	84,000	155,826
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	1,531,891	3,714,518