Summary Of Segment Activity (Detail) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
Segment Reporting Information [Line Items]
Revenues from external customers	$ 17,213,757	$ 10,712,306	$ 45,424,208	$ 29,193,827
Income (loss) from operations	393,612	(269,219)	562,885	(1,773,190)
Other significant non-cash items:
Segment assets	95,898,119		95,898,119		36,723,461
Intangible assets	24,031,876		24,031,876		8,661,302
Goodwill, net	22,256,890		22,256,890		13,046,358
Expenditures for segment assets	798,206		1,242,792
Electro- Mechanical Segment
Segment Reporting Information [Line Items]
Revenues from external customers	11,172,196		33,425,562
Income (loss) from operations	1,238,935		3,019,601
Other significant non-cash items:
Segment assets	35,271,498		35,271,498
Intangible assets	8,406,156		8,406,156
Goodwill, net	13,045,687		13,045,687
Expenditures for segment assets	139,400		549,865
Gas Segment
Segment Reporting Information [Line Items]
Revenues from external customers	6,041,561		11,998,646
Income (loss) from operations	(81,844)		173,327
Other significant non-cash items:
Segment assets	42,265,766		42,265,766
Intangible assets	15,613,439		15,613,439
Goodwill, net	9,211,203		9,211,203
Expenditures for segment assets	658,806		692,927
Other Segment
Segment Reporting Information [Line Items]
Revenues from external customers	0		0
Income (loss) from operations	(763,479)		(2,630,043)
Other significant non-cash items:
Segment assets	18,360,855		18,360,855
Intangible assets	12,281		12,281
Goodwill, net	0		0
Expenditures for segment assets	$ 0		$ 0