CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jul. 01, 2017	Jun. 30, 2018	Jul. 01, 2017
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) [Abstract]
Net income	$ 3,258,477	$ 1,466,402	$ 6,358,672	$ 2,983,543
Other comprehensive income/(loss):
Change in foreign currency translation	(883,246)	411,852	(274,318)	883,823
Change in marketable securities, net of tax benefit of: 2017 - $ $5,553 and $6,345	0	11,620	0	10,169
Change in fair value of interest rate swap, net of tax benefit/(cost) of: 2018 - $59,166 and $19,202 respectively 2017 - $41,680	60,806	(68,005)	226,645	(68,005)
Change in pension and postretirement benefit costs, net of taxes of: 2018 - $131,685 and $65,843 respectively 2017 - $225,727 and $112,864, respectively	222,724	206,683	445,449	413,366
Total other comprehensive income	(599,716)	562,150	397,776	1,239,353
Comprehensive income	$ 2,658,761	$ 2,028,552	$ 6,756,448	$ 4,222,896

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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