Stock Based Compensation - Summary of Unvested Options and Changes During the Year (Detail) (USD $)	6 Months Ended
	Jun. 30, 2013	Dec. 31, 2011
Share Based Compensation Arrangement By Share Based Payment Award Non Vested Options Outstanding Roll Forward [Abstract]
Outstanding at beginning of period, shares	581,888	587,342
Outstanding at end of period, shares	564,783	587,342
Intrinsic value, Beginning of period	$ 193,447
Intrinsic Value, Granted
Intrinsic Value, Forfeited
Intrinsic Value, Vested during the period
Intrinsic value, Unvested options at June 30, 2013	$ 105,286
Unvested Options [Member]
Share Based Compensation Arrangement By Share Based Payment Award Non Vested Options Outstanding Roll Forward [Abstract]
Outstanding at beginning of period, shares	186,655
Granted	0
Forfeited	(271)
Vested during the period	(78,074)
Outstanding at end of period, shares	108,310