INCOME TAXES. (Details) (USD $)	12 Months Ended
	Dec. 27, 2014	Dec. 28, 2013	Dec. 29, 2012
Federal:
Current	$ 2,242,641	$ 4,102,557	$ 988,639
Deferred	1,100,487	1,253,385	372,886
Federal income tax expense (benefit)	3,343,128	5,355,942	1,361,525
State:
Current	227,648	761,633	(98,554)
Deferred	429,879	(194,216)	(1,198,336)
State income tax expense (benefit)	657,527	567,417	(1,296,890)
Total	4,000,655	5,923,359	64,635
Deferred tax assets:
Receivables		20,020	20,020
Inventories		550,170	937,161
Accrued liabilities		1,295,798	1,687,924
Net operating losses and credit carryforwards		1,336,649	1,615,046
Other		166,347	186,864
Total deferred tax assets		3,368,984	4,447,015
Deferred tax liabilities:
Depreciation		(4,357,310)	(3,862,862)
Prepaids and other		(775,759)	(817,871)
Total deferred tax liabilities		(5,133,069)	(4,680,733)
Net deferred tax assets (liabilities)		(1,764,085)	(233,718)
State
Tax loss carryforwards
Tax loss carryforwards	$ 25,000,000