CONSOLIDATED STATEMENTS OF INCOME AND COMPREHENSIVE INCOME - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Income Statement [Abstract]
Revenue	$ 83,929,270	$ 81,283,148
Cost of sales	65,765,007	62,637,232
Gross profit	18,164,263	18,645,916
Selling, general and administrative expenses	9,528,883	8,449,594
Income from operations	8,635,380	10,196,322
Other expense:
Other income (expense)	28,709	(19,774)
Interest expense	(1,989,417)	(1,698,914)
Total other expense, net	(1,960,708)	(1,718,688)
Income before provision for income taxes	6,674,672	8,477,634
Provision for income taxes	4,463,109	2,710,000
Net income	2,211,563	5,767,634
Other comprehensive income (loss), net of tax
Change in unrealized (gain) loss-interest rate swap	14,800	(5,800)
Comprehensive income	$ 2,226,363	$ 5,761,834
Income per common share-basic (in dollars per share)	$ .23	$ 0.65
Income per common share-diluted (in dollars per share)	$ .23	$ 0.65
Shares used in computing earnings per common share:
Basic (in shares)	9,480,948	8,831,064
Diluted (in shares)	9,489,630	8,838,445