Stock Based Compensation - Additional Information (Detail) (USD $)	3 Months Ended		9 Months Ended			9 Months Ended			1 Months Ended		9 Months Ended						1 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2011	Sep. 30, 2012 Restricted Stock	Dec. 31, 2011 Restricted Stock	Sep. 30, 2012 Common Stock	Aug. 31, 2012 Equity Incentive Plan Twenty Twelve	Sep. 30, 2012 Equity Incentive Plan Twenty Twelve	Sep. 30, 2012 Equity Incentive Plan Twenty Twelve Restricted Stock	Sep. 30, 2011 Equity Incentive Plan Twenty Twelve Restricted Stock	Sep. 30, 2012 Equity Incentive Plan Twenty Twelve Restricted Stock Minimum	Sep. 30, 2012 Equity Incentive Plan Twenty Twelve Restricted Stock Maximum	Sep. 30, 2012 Equity Incentive Plan Twenty Twelve Non Vested Stock Options	Sep. 30, 2011 Equity Incentive Plan Twenty Twelve Non Vested Stock Options	Aug. 31, 2012 Previously Approved Plans	Sep. 30, 2012 Previously Approved Plans Restricted Stock	Sep. 30, 2012 Previously Approved Plans Non Vested Stock Options	Sep. 30, 2011 Previously Approved Plans Non Vested Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares initially authorized for issuance under equity incentive plan									300,000
Additional shares authorized for issuance under equity incentive plan									17,666
Shares ceased to be issuable																	17,666
Outstanding options to purchase shares of common stock	433,000		433,000		546,001
Unvested restricted shares outstanding						317,001
Outstanding shares remained available for future grants										319,333
Restricted shares outstanding						317,001	232,501											0
Weighted average grant-date fair values of options granted			$ 1.28	$ 1.97
Aggregate intrinsic value			$ 3,500	$ 21,007		$ 665,700
Vesting period													3 years	4 years
Share-base compensation expense	114,000	105,000	333,000	330,000
Unrecognized compensation cost related to the nonvested options											$ 700,000	$ 793,000			$ 9,000	$ 24,504			$ 9,000	$ 24,504
Unrecognized compensation costs are expected to be recognized over a weighted average period (years)											1 year 8 months 12 days	1 year 7 months 6 days			1 year	6 months
Common stock outstanding								433,000
Restricted shares outstanding																		317,001