Annual report pursuant to Section 13 and 15(d)

Stockholders' Equity - Additional Information (Detail)

v2.4.0.6
Stockholders' Equity - Additional Information (Detail) (USD $)
12 Months Ended
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
Stockholders Equity Note [Line Items]      
Number of shares of common stock to be purchased by issuing warrants 250,000    
Exercise price of stock warrants 9.60    
Warrants expiration date Oct. 14, 2015    
Fair value of warrants outstanding $ 2,000,000 $ 883,000  
Dividend yield         
Stock warrants [Member]
     
Stockholders Equity Note [Line Items]      
Percentage of weighted average expected stock volatility for warrant 111.46%    
Contract term of expected life assumption 5 years    
Percentage of risk free rate for warrant 2.07%    
Dividend yield 0.00%    
Stock warrants [Member] | Remeasuring [Member]
     
Stockholders Equity Note [Line Items]      
Percentage of weighted average expected stock volatility for warrant 46.82%    
Contract term of expected life assumption 2 years 9 months 18 days    
Percentage of risk free rate for warrant 0.45%    
Dividend yield 0.00%    
Increase in fair value of warrants $ 23,000