LONG-TERM DEBT - Interest Expense (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
LONG-TERM DEBT
Interest expense	$ 8,655,000	$ 7,034,000	$ 6,804,000
Amortization of Loan Costs	495,438	509,263	828,075
Amortization of Discount on Convertible Notes	1,273,436	1,194,714	1,120,859
Capitalized Interest		(215,000)
Total Interest Expense	10,423,000	8,523,000	8,753,000
Total Interest Paid	$ 8,419,000	$ 7,060,000	6,779,000
Write off of unamortized loan costs			367,000
Buyers' assumption of existing mortgage loan			$ 23,100,000