Annual report pursuant to Section 13 and 15(d)

Goodwill and Intangible Assets - Intangible Assets (Details)

v2.4.0.6
Goodwill and Intangible Assets - Intangible Assets (Details) (USD $)
 12 Months Ended 9 Months Ended 12 Months Ended 9 Months Ended
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
Dec. 31, 2012
Customer contracts
Energy efficiency expenses
Dec. 31, 2011
Customer contracts
Energy efficiency expenses
Dec. 31, 2012
Customer relationships, non-compete agreements, technology, and trade name
General, administrative and other expenses
Dec. 31, 2011
Customer relationships, non-compete agreements, technology, and trade name
General, administrative and other expenses
Dec. 31, 2012
Other U.S Regions
Customer contracts
Dec. 31, 2012
Other U.S Regions
Customer relationships
Dec. 31, 2012
Other U.S Regions
Non-compete agreements
Dec. 31, 2012
Other U.S Regions
Technology
Dec. 31, 2012
Canada
Customer contracts
Dec. 31, 2012
Canada
Customer relationships
Dec. 31, 2012
Canada
Non-compete agreements
Dec. 31, 2012
Canada
Technology
Dec. 31, 2012
Canada
Trade names
Dec. 31, 2012
All Other
Customer contracts
Dec. 31, 2012
All Other
Customer relationships
Dec. 31, 2012
All Other
Non-compete agreements
Dec. 31, 2012
All Other
Technology
Dec. 31, 2012
All Other
Trade names
Dec. 31, 2012
Minimum
Customer contracts
Sep. 30, 2012
Minimum
Customer relationships, non-compete agreements, technology, and trade name
Dec. 31, 2012
Maximum
Customer contracts
Sep. 30, 2012
Maximum
Customer relationships, non-compete agreements, technology, and trade name
Finite-Lived Intangible Assets [Line Items]                                                  
Intangible assets amortization period                                           1 year 4 years 5 years 14 years
Intangible Assets, Net [Roll Forward]                                                  
Beginning Balance $ 12,727,528             $ 1,060,433 $ 3,240,593 $ 1,393,575 $ 200,582 $ 0 $ 0 $ 0 $ 0 $ 0 $ 2,551,124 $ 2,073,478 $ 398,222 $ 1,386,506 $ 423,015        
Acquisitions 2,281,240             0 0 0 0 776,875 310,317 282,115 655,924 74,759 0 0 87,250 94,000 0        
Amortization of intangible assets (5,282,170)             (1,060,433) (1,101,624) (550,340) (51,920) (147,331) (6,338) (73,730) (71,996) (5,310) (1,242,414) (157,144) (99,556) (546,738) (167,296)        
Foreign Currency Translation 16,280             0 0 0 0 4,845 1,498 2,759 6,438 740 0 0 0 0 0        
Ending Balance 9,742,878 12,727,528           0 2,138,969 843,235 148,662 634,389 305,477 211,144 590,366 70,189 1,308,710 1,916,334 385,916 933,768 255,719        
Amortization of intangible assets $ 5,282,170 $ 1,752,472 $ 0 $ 2,450,178 $ 1,364,443 $ 2,831,992 $ 388,029