COMMITMENTS AND CONTINGENCIES. (Details) (USD $)	12 Months Ended
	Dec. 29, 2012	Dec. 31, 2011	Dec. 25, 2010
Lease Commitments and Related Party Transactions
Related party rent expense	$ 658,000	$ 683,000	$ 683,000
Rent expense under all operating leases	733,340	758,834	713,615
2013	39,250
2014	27,000
2015	27,000
2016	9,000
Aggregated future minimum rental payments under noncancelable operating leases	102,250
Consigned Inventories
Consigned inventories to the Company	26,000,000	22,300,000
Period within which chassis are converted and delivered to customers	90 days
Repurchase Commitments
Maximum potential repurchase liability	1,900,000	4,800,000
Self insurance
Portion of general liability for which the entity is self-insured, per occurrence	100,000	100,000
Self insurance for employee health benefits, annual coverage per employee	200,000
Worker's compensation liability for which the entity is self insured, per occurrence	$ 250,000