CONDENSED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (LOSS) (Unaudited)) - USD ($)	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Income Statement [Abstract]
Revenue	$ 20,032,701	$ 12,670,032
Cost of sales	15,495,187	24,309,136
Gross profit (loss)	4,537,514	(11,639,104)
Selling, general and administrative expenses	2,163,878	2,720,383
Income (loss) from operations	2,373,636	(14,359,487)
Interest expense	390,335	275,733
Income (loss) before provision for (benefit from) income taxes	1,983,301	(14,635,220)
Provision for (benefit from) income taxes	734,000	(5,415,000)
Net income (loss)	1,249,301	(9,220,220)
Other comprehensive income (loss), net of tax
Change in unrealized gain-interest rate swap	5,200	3,453
Comprehensive income (loss)	$ 1,254,501	$ (9,216,767)
Income (loss) per common share - basic (in dollars per share)	$ 0.14	$ (1.07)
Income (loss) per common share - diluted (in dollars per share)	$ 0.14	$ (1.07)
Shares used in computing income (loss) per common share:
Basic (shares)	8,781,292	8,596,538
Diluted (shares)	8,830,953	8,596,538