CONSOLIDATED STATEMENTS OF CHANGES IN PARTNERS' CAPITAL (USD $)	Total USD ($)	Subtotal	Class A USD ($)	Class B USD ($)	General Partnership USD ($)	Treasury Units
Balance at Dec. 31, 2011	$ (21,310,852)		$ (17,052,134)	$ (4,045,783)	$ (212,935)
Balance (in units) at Dec. 31, 2011	131,484	180,225	144,180	34,243	1,802	48,741
Increase (Decrease) in Partners' Capital
Distribution to Partners	(1,971,689)		(1,577,351)	(374,621)	(19,717)
Stock Buyback	(69,379)		(55,778)	(12,921)	(680)
Stock Buyback (in units)	(86)					86
Net Income	1,674,214		1,339,372	318,101	16,742
Balance at Jun. 30, 2012	(21,677,705)		(17,345,891)	(4,115,224)	(216,590)
Balance (in units) at Jun. 30, 2012	131,398	180,225	144,180	34,243	1,802	48,827
Balance at Dec. 31, 2012	(22,515,678)		(18,017,082)	(4,273,666)	(224,929)
Balance (in units) at Dec. 31, 2012	130,444	180,225	144,180	34,243	1,802	49,781
Increase (Decrease) in Partners' Capital
Distribution to Partners	(1,950,596)		(1,560,476)	(370,614)	(19,506)
Stock Buyback	(399,487)		(321,240)	(74,335)	(3,912)
Stock Buyback (in units)	(404)					404
Net Income	5,370,742		4,296,594	1,020,441	53,707
Balance at Jun. 30, 2013	$ (19,495,018)		$ (15,602,204)	$ (3,698,174)	$ (194,640)
Balance (in units) at Jun. 30, 2013	130,040	180,225	144,180	34,243	1,802	50,185