QUARTERLY FINANCIAL DATA (UNAUDITED) (Details)	3 Months Ended								12 Months Ended
	Dec. 31, 2021 USD ($) $ / shares $ / item	Sep. 30, 2021 USD ($) $ / shares $ / item	Jun. 30, 2021 USD ($) $ / shares $ / item	Mar. 31, 2021 USD ($) $ / shares $ / item	Dec. 31, 2020 USD ($) $ / shares $ / item	Sep. 30, 2020 USD ($) $ / shares $ / item	Jun. 30, 2020 USD ($) $ / shares $ / item	Mar. 31, 2020 USD ($) $ / shares $ / item	Dec. 31, 2021 USD ($) $ / shares $ / item	Dec. 31, 2020 USD ($) $ / shares $ / item	Dec. 31, 2019 USD ($) $ / shares
QUARTERLY FINANCIAL DATA (UNAUDITED)
Revenue	$ 16,155,649	$ 15,946,672	$ 15,447,344	$ 15,088,789	$ 14,825,754	$ 15,142,266	$ 15,759,106	$ 16,375,584	$ 62,638,454	$ 62,102,710	$ 60,477,314
Expenses	13,046,756	12,395,436	11,260,112	11,693,650	11,873,260	11,914,630	11,314,637	12,031,150	48,395,954	47,133,677
Income Before Other Income (Expense)	3,108,893	3,551,236	4,187,232	3,395,139	2,952,494	3,227,636	4,444,469	4,344,434	14,242,500	14,969,033	17,271,767
Other Expenses	(6,009,382)	(3,626,621)	(3,617,341)	(3,689,319)	(3,922,516)	(3,666,920)	(2,979,418)	(2,975,651)	(16,942,663)	(13,544,505)	(10,724,515)
Net (Loss) Income	$ (2,900,489)	$ (75,385)	$ 569,891	$ (294,180)	$ (970,022)	$ (439,284)	$ 1,465,051	$ 1,368,783	$ (2,700,163)	$ 1,424,528	$ 6,547,252
Net Income (loss) per Unit (in dollars per unit) | $ / shares	$ (23.83)	$ (0.62)	$ 4.68	$ (2.42)	$ (7.95)	$ (3.61)	$ 12.03	$ 11.23	$ (22.19)	$ 11.70	$ 53.48
Net Income (loss) per Depositary Receipt (in dollars per receipt) | $ / item	(0.79)	(0.02)	0.16	(0.08)	(0.27)	(0.12)	0.40	0.37	(0.74)	0.39