CONSOLIDATED CONDENSED STATEMENTS OF COMPREHENSIVE INCOME (USD $)	3 Months Ended
Mar. 28, 2015	Mar. 29, 2014
CONSOLIDATED CONDENSED STATEMENTS OF COMPREHENSIVE INCOME
NET INCOME	$ 6,054,300	$ 4,551,900
Unrealized net gains (losses) on marketable securities:
Unrealized holding net gains (losses) arising during period	48,700	(12,000)
Reclassification adjustment for net gains included in net income	(2,300)	(3,800)
OTHER COMPREHENSIVE INCOME (LOSS), BEFORE TAX	46,400	(15,800)
Unrealized net gains/losses on marketable securities:
Unrealized holding net gains/losses arising during period	(18,500)	4,600
Reclassification adjustment for net gains included in net income	900	1,400
INCOME TAX (EXPENSE) BENEFIT RELATED TO ITEMS OF OTHER COMPREHENSIVE INCOME	(17,600)	6,000
OTHER COMPREHENSIVE INCOME (LOSS), NET OF TAX	28,800	(9,800)
COMPREHENSIVE INCOME	$ 6,083,100us-gaap_ComprehensiveIncomeNetOfTax	$ 4,542,100us-gaap_ComprehensiveIncomeNetOfTax

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount before tax of other comprehensive income (loss) attributable to parent entity.

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