CONSOLIDATED STATEMENTS OF CHANGES IN PARTNER'S CAPITAL - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Increase (Decrease) in Partners' Capital
Balance			$ (37,823,787)	$ (35,624,010)
Balance (in units)			121,978	124,386
Distribution to Partners			$ (3,506,894)	$ (3,525,701)
Stock Buyback			$ (394,031)	$ (3,680,570)
Stock Buyback (in units)			(222)	(2,205)
Net income	$ (439,284)	$ 1,383,979	$ 2,394,551	$ 4,648,739
Balance	$ (39,330,161)	$ (38,181,542)	$ (39,330,161)	$ (38,181,542)
Balance (in units)	121,756	122,181	121,756	122,181
Subtotal
Increase (Decrease) in Partners' Capital
Balance (in units)			180,225	180,225
Balance (in units)	180,225	180,225	180,225	180,225
General Partnership
Increase (Decrease) in Partners' Capital
Balance			$ (376,827)	$ (354,833)
Balance (in units)			1,802	1,802
Distribution to Partners			$ (35,069)	$ (35,257)
Stock Buyback			(3,941)	(36,803)
Net income			23,946	46,487
Balance	$ (391,891)	$ (380,406)	$ (391,891)	$ (380,406)
Balance (in units)	1,802	1,802	1,802	1,802
Treasury Units
Increase (Decrease) in Partners' Capital
Balance (in units)			(58,247)	(55,839)
Stock Buyback (in units)			(222)	(2,205)
Balance (in units)	(58,469)	(58,044)	(58,469)	(58,044)
Class A
Increase (Decrease) in Partners' Capital
Balance			$ (30,287,245)	$ (28,527,352)
Balance (in units)			144,180	144,180
Distribution to Partners			$ (2,805,515)	$ (2,820,561)
Stock Buyback			(315,220)	(2,944,508)
Net income			1,915,640	3,718,992
Balance	$ (31,492,340)	$ (30,573,429)	$ (31,492,340)	$ (30,573,429)
Balance (in units)	144,180	144,180	144,180	144,180
Class B
Increase (Decrease) in Partners' Capital
Balance			$ (7,159,715)	$ (6,741,825)
Balance (in units)			34,243	34,243
Distribution to Partners			$ (666,310)	$ (669,883)
Stock Buyback			(74,870)	(699,259)
Net income			454,965	883,260
Balance	$ (7,445,930)	$ (7,227,707)	$ (7,445,930)	$ (7,227,707)
Balance (in units)	34,243	34,243	34,243	34,243