Quarterly Operating Results (Schedule Of Quarterly Operations) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Quarterly Operating Results [Abstract]
Revenue	$ 14,306	$ 14,666	$ 16,177	$ 15,903	$ 15,082	$ 15,462	$ 17,834	$ 16,679	$ 61,052	$ 65,057	$ 55,453
Operating expenses	13,412	14,386	14,562	13,825	13,202	14,266	14,876	14,561	56,185	56,905	52,177
Operating income	894	280	1,615	2,078	1,880	1,196	2,958	2,118	4,867	8,152	3,276
Net gain (loss) on dispositions of assets	(45)	(14)	(16)	39	(17)	3,716	1,895	(24)	(36)	5,570	6,807
Equity in earnings (loss) of joint venture	(405)	(84)	166	513	(469)	(41)	63	229	190	(218)	190
Net gain (loss) on derivatives and convertible debt	(155)	(223)	(456)	(237)	(402)	116	156	447	(1,071)	317	436
Other expense	(24)	(27)	(24)	(29)	(26)	(23)	(20)	(14)	(104)	(83)	(111)
Interest expense	(1,807)	(1,912)	(2,094)	(2,163)	(2,153)	(2,154)	(2,091)	(1,928)	(7,976)	(8,326)	(5,174)
Impairment recovery (loss), net								93		93	(2,151)
Earnings (loss) before income taxes	(1,542)	(1,980)	(809)	201	(1,187)	2,810	2,961	921	(4,130)	5,505	2,306
Income tax benefit (expense)	(282)	(8)	(461)	(186)	(20)	(132)	(54)	(129)	(937)	(335)	595
Net earnings (loss)	(1,824)	(1,988)	(1,270)	15	(1,207)	2,678	2,907	792	(5,067)	5,170	2,901
(Earning) loss attributable to noncontrolling interest	2	10	6	1	242	(20)	(21)	(6)	19	195	(20)
Net earnings (loss) attributable to controlling interests	(1,822)	(1,978)	(1,264)	16	(965)	2,658	2,886	786	(5,048)	5,365	2,881
Dividends declared and undeclared and in kind dividends deemed on preferred stock	(144)	(145)	(144)	(145)	(144)	(145)	(145)	(144)	(578)	(578)	(12,243)
Net earnings (loss) attributable to common shareholders	$ (1,966)	$ (2,123)	$ (1,408)	$ (129)	$ (1,109)	$ 2,513	$ 2,741	$ 642	$ (5,626)	$ 4,787	$ (9,362)
Earnings (loss) per Share
Total - Basic Earnings (Loss) per Share	$ (0.17)	$ (0.18)	$ (0.12)	$ (0.01)	$ (0.10)	$ 0.21	$ 0.23	$ 0.05	$ (0.48)	$ 0.40	$ (1.00)
Total - Diluted Earnings (Loss) per Share	$ (0.17)	$ (0.18)	$ (0.12)	$ (0.01)	$ (0.10)	$ 0.21	$ 0.23	$ 0.05	$ (0.48)	$ 0.40	$ (1.00)