CONSOLIDATED STATEMENTS OF CHANGES IN PARTNER'S CAPITAL - USD ($)	3 Months Ended		139 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019
Increase (Decrease) in Partners' Capital
Balance	$ (35,624,010)	$ (35,315,177)
Balance (in units)	124,386	124,386
Distribution to Partners	$ (1,177,353)	$ (1,119,481)
Stock Buyback	$ (2,930,736)		$ (43,205,000)
Stock Buyback (in units)	(1,795)
Net income	$ 1,500,516	1,878,558
Balance	$ (38,231,583)	$ (34,556,100)	$ (38,231,583)
Balance (in units)	122,591	124,386	122,591
Subtotal
Increase (Decrease) in Partners' Capital
Balance (in units)	180,225	180,225
Balance (in units)	180,225	180,225	180,225
General Partnership
Increase (Decrease) in Partners' Capital
Balance	$ (354,833)	$ (351,745)
Balance (in units)	1,802	1,802
Distribution to Partners	$ (11,774)	$ (11,195)
Stock Buyback	$ (29,307)
Stock Buyback (in units)	(18)
Net income	$ 15,005	18,786
Balance	$ (380,909)	$ (344,154)	$ (380,909)
Balance (in units)	1,802	1,802	1,802
Treasury Units
Increase (Decrease) in Partners' Capital
Balance (in units)	(55,839)	(55,839)
Stock Buyback (in units)	(1,795)
Balance (in units)	(57,634)	(55,839)	(57,634)
Class A
Increase (Decrease) in Partners' Capital
Balance	$ (28,527,352)	$ (28,280,285)
Balance (in units)	144,180	144,180
Distribution to Partners	$ (941,882)	$ (895,585)
Stock Buyback	(2,344,601)
Net income	1,200,413	1,502,846
Balance	$ (30,613,422)	$ (27,673,024)	$ (30,613,422)
Balance (in units)	144,180	144,180	144,180
Class B
Increase (Decrease) in Partners' Capital
Balance	$ (6,741,825)	$ (6,683,147)
Balance (in units)	34,243	34,243
Distribution to Partners	$ (223,697)	$ (212,701)
Stock Buyback	(556,828)
Net income	285,098	356,926
Balance	$ (7,237,252)	$ (6,538,922)	$ (7,237,252)
Balance (in units)	34,243	34,243	34,243