Employee Benefit Plans (Detail) - Reserved shares of Common Stock	6 Months Ended
	Jun. 30, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total	1,397,809
Stock options granted but not exercised [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted but not exercised	20,000
Restricted stock to non-employees (authorized but not granted)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock to employees, non-employees and executives	39,797
Restricted stock to employees and executives (authorized but not granted)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock to employees, non-employees and executives	1,338,012