QUARTERLY FINANCIAL DATA (UNAUDITED) (Details) - USD ($)	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 24, 2017	Jun. 25, 2017	Mar. 26, 2017	Dec. 25, 2016	Sep. 25, 2016	Jun. 26, 2016	Mar. 27, 2016	Dec. 31, 2017	Dec. 25, 2016	Dec. 27, 2015
Quarterly Financial Information Disclosure [Abstract]
Revenues	$ 75,700,827	$ 71,281,674	$ 68,773,862	$ 56,843,687	$ 64,278,864	$ 67,407,350	$ 62,615,014	$ 59,550,986	$ 272,600,050	$ 253,852,214	$ 217,533,856
Gross Profit	19,255,426	18,248,059	17,227,279	13,671,234	15,110,323	16,431,888	15,184,525	13,346,630	68,401,998	60,073,366	47,906,706
Loss on extinguishment of debt					0	0	(404,119)	0	0	(404,119)	(438,507)
Income before income taxes	3,875,844	4,752,516	3,744,537	2,134,737	3,739,261	3,764,628	2,283,688	1,382,504	14,507,634	11,170,081	8,715,408
Net income	$ (874,786)	$ 3,136,863	$ 2,284,526	$ 1,301,831	$ 2,303,933	$ 2,347,855	$ 1,397,481	$ 833,138	$ 5,848,434	$ 6,882,407	$ 5,347,408
Net income (loss) per share:
Basic (in dollars per share)	$ (0.10)	$ 0.36	$ 0.26	$ 0.15	$ 0.27	$ 0.27	$ 0.18	$ 0.11	$ 0.67	$ 0.85	$ 0.76
Diluted (in dollars per share)	$ (0.10)	$ 0.35	$ 0.25	$ 0.15	$ 0.26	$ 0.26	$ 0.17	$ 0.11	$ 0.65	$ 0.82	$ 0.73
Weighted-average shares outstanding:
Basic (in shares)	8,759,376	8,759,376	8,746,100	8,668,955	8,668,485	8,658,061	7,711,050	7,388,536	8,733,941	8,107,637	7,079,459
Weighted-average number of diluted common shares outstanding	8,759,376	9,077,147	9,050,596	8,924,419	8,930,542	9,028,398	8,052,996	7,646,726	9,038,187	8,399,883	7,288,705