Consolidated Statements of Income - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Revenue
Electrical construction	$ 109,154,476	$ 125,771,361
Other	4,799,043	4,652,102
Total revenue	113,953,519	130,423,463
Costs and expenses
Electrical construction	86,714,412	93,566,045
Other	3,147,791	3,242,887
Selling, general and administrative	6,611,315	5,913,132
Depreciation and amortization	7,217,901	6,312,164
Loss (gain) on sale of property and equipment	76,810	(17,535)
Total costs and expenses	103,768,229	109,016,693
Total operating income	10,185,290	21,406,770
Other income (expense), net
Interest income	31,696	33,465
Interest expense, net of amount capitalized	(665,268)	(591,176)
Other income, net	57,654	68,465
Total other expense, net	(575,918)	(489,246)
Income from continuing operations before income taxes	9,609,372	20,917,524
Income tax provision	1,035,997	7,809,768
Income from continuing operations	8,573,375	13,107,756
Loss from discontinued operations, net of income tax benefit of $164,235 and $66,077, respectively	(275,624)	(108,007)
Net income	$ 8,297,751	$ 12,999,749
Net income (loss) per share of common stock — basic and diluted
Continuing operations (usd per share)	$ 0.34	$ 0.52
Discontinued operations (usd per share)	(0.01)	0.00
Net (loss) income (usd per share)	$ 0.33	$ 0.51
Weighted average shares outstanding - basic and diluted (shares)	25,451,354	25,451,354