Consolidated Statement of Stockholders' Equity (USD $)
Total
Common Stock [Member]
Additional Paid-in Capital [Member]
Retained Earnings [Member]
Stockholders' equity at beginning of period at Dec. 31, 2013 $ 159,230,031 $ 2,291 $ 106,831,802 $ 52,395,938
Common stock, shares at beginning of period at Dec. 31, 2013 22,900,471 22,900,471    
Increase (decrease) in stockholders' equity:        
Share compensation expense 3,351,598   3,351,598  
Exercise of stock options (in shares)   54,839    
Exercise of stock options 563,679 6 563,673  
Common stock issued for vested restricted stock (in shares)   156,012    
Common stock issued for vested restricted stock 0 16 (16)  
Common shares withheld and retired to satisfy employee tax witholding obligations upon vesting of restricted stock (in shares)   (44,493)    
Common shares withheld and retired to satisfy employee tax withholding obligations upon vesting of restricted stock (872,443) (4) (872,439)  
Tax benefit from exercise of stock options 297,451   297,451  
Net income 12,131,780     12,131,780
Stockholders' equity at end of period at Sep. 30, 2014 $ 174,702,096 $ 2,309 $ 110,172,069 $ 64,527,718
Common stock, shares at end of period at Sep. 30, 2014 23,066,829 23,066,829