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NOTES PAYABLE AND LONG-TERM DEBT (Narrative) (Details) - USD ($)	3 Months Ended		12 Months Ended
	Mar. 31, 2020	Mar. 31, 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	$ 754,000		$ 65,000
Unrealized gain on interest rate swap	(545,000)	$ 25,000	134,000
Securities on deposit	1,232,000		294,000
Collateral Pledged [Member]
Debt Instrument [Line Items]
Available-for-sale securities pledged as collateral	$ 1,232,000		$ 294,000
Cash flow hedging
Debt Instrument [Line Items]
Cash flow hedge, liability at fair value					$ 566,000
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						$ 188,000
Interest rate swap
Debt Instrument [Line Items]
Derivative, notional amount				$ 9,000,000
Derivative, fixed interest rate				5.28%