Earnings Per Share - Additional Information (Detail) (USD $)	9 Months Ended	12 Months Ended		12 Months Ended				0 Months Ended	1 Months Ended	12 Months Ended		1 Months Ended
	Sep. 30, 2013	Dec. 31, 2012	Apr. 15, 2013	Dec. 31, 2012 Stock Options1	Dec. 31, 2011 Stock Options1	Dec. 31, 2012 Stock Options 2	Dec. 31, 2011 Stock Options 2	Jan. 10, 2013 Warrant	Jan. 31, 2013 Warrant	Dec. 31, 2009 Warrant	Dec. 31, 2008 Warrant	Jan. 31, 2011 Warrant 1	Jan. 31, 2011 Warrant 2
Earnings Per Share Disclosure [Line Items]
Warrants issued	2,800,000							2,800,000	300,000	969,358	125,000	150,000	144,000
Warrants issued, exercise price			1.80						1.80	0.996	1.196	3.25	3.99
Options outstanding	3,040,000	3,040,000
Options Granted				1,300,000	120,000	120,000	1,500,000
Options Granted, exercise price				$ 1.22	$ 2.27	$ 1.49	$ 2.59
Options granted weighted average number of diluted shares outstanding	1,300,000
Antidilutive securities excluded from computation of earnings per share, amount		120,000