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Amount of investment in marketable security.

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Amount, after tax and reclassification, of gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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NOTES PAYABLE AND LONG-TERM DEBT (Narrative) (Details) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020	Feb. 26, 2020
Debt Instrument [Line Items]
Cash flow hedge, derivative instrument liabilities at fair value			$ 619,000
Unrealized gain (loss) on interest rate swap	$ 489,000	$ (545,000)	438,000
Securities on deposit			957,000
Collateral Pledged [Member]
Debt Instrument [Line Items]
Available-for-sale securities pledged as collateral			957,000
Interest rate swap
Debt Instrument [Line Items]
Derivative, notional amount				$ 3,000,000
Derivative, fixed interest rate				4.93%
Cash flow hedge, liability at fair value			155,000
Interest rate swap
Debt Instrument [Line Items]
Derivative, notional amount				$ 9,000,000
Derivative, fixed interest rate				5.28%
Cash flow hedge, liability at fair value			$ 464,000