CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) (Parenthetical) - USD ($)	3 Months Ended	9 Months Ended
Oct. 02, 2021	Oct. 03, 2020	Oct. 02, 2021	Oct. 03, 2020
Other comprehensive income/(loss):
Change in fair value of interest rate swap and marketable securities, tax benefit	$ 31,759	$ (35,587)	$ 188,753	$ 547,087
Change in pension and postretirement benefit costs, income tax expense	$ 107,962	$ 81,144	$ 308,117	$ 243,429

Amount, after reclassification adjustment, of tax (expense) benefit for (increase) decrease in accumulated other comprehensive income of defined benefit plan.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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