Earnings Per Share (Schedule Of Calculation Of Numerator And Denominator In Earnings Per Share) (Details) - USD ($)	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Earnings Per Share [Abstract]
Net income	$ 4,736,000	$ 6,305,000	$ 9,937,000	$ (16,620,000)	$ 5,680,000	$ 6,417,000	$ (4,389,000)	$ 11,945,000	$ 4,358,000	$ 19,653,000	$ 8,764,000
Preferred stock dividends									(10,863,000)	(13,652,000)	(14,408,000)
Preferred stock redemptions costs									(3,507,000)	(7,890,000)
Net (income) loss attributable to noncontrolling interests									(469,000)	(510,000)	179,000
Net earnings allocated to unvested shares									(628,000)	(754,000)	(715,000)
Net loss attributable to vested common shares									$ (11,109,000)	$ (3,153,000)	$ (6,180,000)
Weighted average number of vested common shares outstanding, basic and diluted									88,420,000	84,168,000	81,672,000
Net loss per common share attributable to common shareholders, basic and diluted	$ 0.02	$ 0.04	$ 0.08	$ (0.26)	$ 0.03	$ (0.06)	$ (0.10)	$ 0.10	$ (0.13)	$ (0.04)	$ (0.08)