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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		6 Months Ended		12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019	Feb. 26, 2020	Dec. 31, 2011	Dec. 31, 2010	May 26, 2010
Debt Instrument [Line Items]
Cash flow hedge, derivative instrument liabilities at fair value	$ 848,000		$ 848,000		$ 65,000
Unrealized gain (loss) on interest rate swap	(74,000)	$ 20,000	(619,000)	$ 45,000	134,000
Securities on deposit	1,228,000		1,228,000		294,000
Collateral Pledged [Member]
Debt Instrument [Line Items]
Available-for-sale securities pledged as collateral	$ 1,228,000		$ 1,228,000		$ 294,000
Cash flow hedging
Debt Instrument [Line Items]
Cash flow hedge, liability at fair value							$ 636,000
Interest rate swap
Debt Instrument [Line Items]
Derivative, notional amount						$ 3,000,000			$ 9,000,000
Derivative, fixed interest rate						4.93%			8.49%
Cash flow hedge, liability at fair value								$ 212,000
Interest rate swap
Debt Instrument [Line Items]
Derivative, notional amount						$ 9,000,000
Derivative, fixed interest rate						5.28%