Annual report pursuant to Section 13 and 15(d)

Goodwill and Intangible Assets - Goodwill (Details)

v2.4.0.6
Goodwill and Intangible Assets - Goodwill (Details) (USD $)
12 Months Ended
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
Goodwill [Roll Forward]      
Beginning Balance $ 47,881,346 $ 20,580,995  
Acquisitions 2,021,260 26,823,070  
Foreign Currency Translation and Other Adjustments (934,216) 477,281  
Ending Balance 48,968,390 47,881,346 20,580,995
Impairment of goodwill 1,016,325 0 0
U.S Federal
     
Goodwill [Roll Forward]      
Beginning Balance 3,374,967 3,374,967  
Acquisitions 0 0  
Foreign Currency Translation and Other Adjustments 0 0  
Ending Balance 3,374,967 3,374,967  
Central U.S Region
     
Goodwill [Roll Forward]      
Beginning Balance 1,972,415 1,972,415  
Acquisitions 0 0  
Foreign Currency Translation and Other Adjustments 0 0  
Ending Balance 1,972,415 1,972,415  
Other U.S Regions
     
Goodwill [Roll Forward]      
Beginning Balance 21,736,140 4,906,875  
Acquisitions 0 16,545,434  
Foreign Currency Translation and Other Adjustments 0 283,831  
Ending Balance 21,736,140 21,736,140  
Canada
     
Goodwill [Roll Forward]      
Beginning Balance 2,874,383 2,680,933  
Acquisitions 1,886,945 0  
Foreign Currency Translation and Other Adjustments (934,216) 193,450  
Ending Balance 3,827,112 2,874,383  
All Other
     
Goodwill [Roll Forward]      
Beginning Balance 17,923,441 7,645,805  
Acquisitions 134,315 10,277,636  
Foreign Currency Translation and Other Adjustments 0 0  
Ending Balance $ 18,057,756 $ 17,923,441