CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) - USD ($)	3 Months Ended	9 Months Ended
Sep. 29, 2018	Sep. 30, 2017	Sep. 29, 2018	Sep. 30, 2017
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) [Abstract]
Net income	$ 3,766,661	$ 2,230,481	$ 10,125,333	$ 5,214,024
Other comprehensive income/(loss):
Change in foreign currency translation	(540,998)	378,509	(815,314)	1,262,332
Change in marketable securities, net of tax benefit of: 2018 - $5,435 and $5,853 respectively 2017 - $22,688 and $17,135 respectively	19,801	31,379	18,383	41,548
Change in fair value of interest rate swap, net of tax benefit/(cost) of: 2018 - $71,428 and $12,263 respectively 2017 - $31,275 and $(10,406) respectively	38,833	16,978	265,480	(51,027)
Change in pension and postretirement benefit costs, net of taxes of: 2018 - $197,527 and $65,842 respectively 2017 - $338,592 and $112,865 respectively	222,725	206,682	668,174	620,048
Total other comprehensive income	(259,639)	633,548	136,723	1,872,901
Comprehensive income	$ 3,507,022	$ 2,864,029	$ 10,262,056	$ 7,086,925

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 increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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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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