QUARTERLY FINANCIAL DATA (UNAUDITED) (Details)	3 Months Ended								12 Months Ended
	Dec. 31, 2024 USD ($) $ / shares $ / item	Sep. 30, 2024 USD ($) $ / shares $ / item	Jun. 30, 2024 USD ($) $ / shares $ / item	Mar. 31, 2024 USD ($) $ / shares $ / item	Dec. 31, 2023 USD ($) $ / shares $ / item	Sep. 30, 2023 USD ($) $ / shares $ / item	Jun. 30, 2023 USD ($) $ / shares $ / item	Mar. 31, 2023 USD ($) $ / shares $ / item	Dec. 31, 2024 USD ($) $ / shares $ / item	Dec. 31, 2023 USD ($) $ / shares $ / item	Dec. 31, 2022 USD ($) $ / shares
QUARTERLY FINANCIAL DATA (UNAUDITED)
Revenue	$ 20,379,550	$ 20,209,035	$ 20,050,566	$ 19,893,399	$ 19,727,004	$ 18,961,642	$ 18,101,036	$ 17,691,686	$ 80,532,550	$ 74,481,368	$ 68,293,726
Expenses	13,768,911	13,738,359	13,512,402	14,141,625	15,001,133	14,062,381	13,362,686	13,240,321	55,161,297	55,666,521
Income Before Other Income (Expense)	6,610,639	6,470,676	6,538,164	5,751,774	4,725,871	4,899,261	4,738,350	4,451,365	25,371,253	18,814,847	18,088,147
Other Expenses	(2,394,772)	(2,561,278)	(2,465,438)	(2,288,178)	(2,426,126)	(2,724,035)	(2,513,746)	(2,696,990)	(9,709,666)	(10,360,897)	(14,364,873)
Net Income	$ 4,215,867	$ 3,909,398	$ 4,072,726	$ 3,463,596	$ 2,299,745	$ 2,175,226	$ 2,224,604	$ 1,754,375	$ 15,661,587	$ 8,453,950	$ 3,723,274
Net Income per Unit (in dollars per unit) | $ / shares	$ 36.11	$ 33.44	$ 34.77	$ 29.51	$ 19.51	$ 18.38	$ 18.73	$ 14.72	$ 133.83	$ 71.34	$ 30.99
Net Income per Depositary Receipt (in dollars per receipt) | $ / item	1.21	1.11	1.16	0.98	0.65	0.61	0.62	0.49	4.46	2.38