Segment Reporting - Segment Reporting (Detail) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
Consolidated revenue from external customers:
Consolidated total revenue	$ 8,738,557	$ 7,605,854	$ 25,331,696	$ 21,584,460
Consolidated loss before income taxes:
Consolidated loss before income taxes	(449,743)	(522,655)	(2,798,173)	(2,172,741)
Consolidated total assets:
Consolidated total assets	51,284,369		51,284,369		55,130,662
Energy Procurement [Member]
Consolidated revenue from external customers:
Consolidated total revenue	7,295,276	5,626,444	21,673,273	17,480,645
Consolidated loss before income taxes:
Consolidated loss before income taxes	(332,233)	(443,278)	(2,131,734)	(1,775,952)
Amortization	943,977	587,772	2,831,927	1,978,902
Depreciation	50,482	49,626	148,309	140,678
Interest expense, net	253,822	61,432	733,956	174,344
Consolidated total assets:
Consolidated total assets	45,566,740		45,566,740		48,839,503
Energy Efficiency Services [Member]
Consolidated revenue from external customers:
Consolidated total revenue	1,443,281	1,979,410	3,658,423	4,103,815
Consolidated loss before income taxes:
Consolidated loss before income taxes	(117,510)	(79,377)	(666,439)	(396,789)
Amortization	39,289	39,289	117,868	127,971
Depreciation	5,891	5,817	18,803	17,835
Interest expense, net		25,485		100,280
Consolidated total assets:
Consolidated total assets	$ 5,717,629		$ 5,717,629		$ 6,291,159