CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) - USD ($)	3 Months Ended	9 Months Ended
Sep. 28, 2019	Sep. 29, 2018	Sep. 28, 2019	Sep. 29, 2018
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) [Abstract]
Net income	$ 4,193,082	$ 3,766,661	$ 8,293,815	$ 10,125,333
Other comprehensive income/(loss):
Change in foreign currency translation	(537,751)	(540,998)	(346,657)	(815,314)
Change in marketable securities, net of tax benefit/(cost) of: 2019 - $176 and $(288) respectively 2018 - $5,853 and $5,435 respectively	538	19,801	(882)	18,383
Change in fair value of interest rate swap, net of tax benefit/(cost) of: 2019 - $15,720 and $85,537 respectively 2018 - $12,263 and $71,428 respectively	(49,780)	38,833	(270,866)	265,480
Change in pension and postretirement benefit costs, net of taxes of: 2019 - $75,138 and $217,014 respectively 2018 - $65,842 and $197,527 respectively	235,859	222,725	681,221	668,174
Total other comprehensive income/(loss)	(351,134)	(259,639)	62,816	136,723
Comprehensive income	$ 3,841,948	$ 3,507,022	$ 8,356,631	$ 10,262,056

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 after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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