Condensed Consolidated Statements of Changes in Equity - USD ($) $ in Thousands	Total	Common stock	Capital in excess of par value	Cumulative net income	Cumulative dividends	Accumulated other comprehensive income/(loss)
Balance at Dec. 31, 2021	$ 235,327	$ 138	$ 268,515	$ 789,559	$ (823,998)	$ 1,113
Balance, Shares at Dec. 31, 2021		13,785
Shares of Beneficial Interest:
Issued	54		54
Issued (in shares)		1
Restricted stock-based compensation expense	223		223
Dividends	(9,719)				(9,719)
Comprehensive income:
Net income	5,405			5,405
Unrealized net gain/(loss) on cash flow hedges	5,684					5,684
Subtotal - comprehensive income	11,089			5,405		5,684
Balance at Mar. 31, 2022	236,974	$ 138	268,792	794,964	(833,717)	6,797
Balance, Shares at Mar. 31, 2022		13,786
Balance at Dec. 31, 2022	229,101	$ 138	269,472	810,661	(863,181)	12,011
Balance, Shares at Dec. 31, 2022		13,803
Shares of Beneficial Interest:
Issued	38		38
Issued (in shares)		1
Restricted stock-based compensation expense	188		188
Dividends	(9,869)				(9,869)
Comprehensive income:
Net income	4,459			4,459
Unrealized net gain/(loss) on cash flow hedges	(1,747)					(1,747)
Subtotal - comprehensive income	2,712			4,459		(1,747)
Balance at Mar. 31, 2023	$ 222,170	$ 138	$ 269,698	$ 815,120	$ (873,050)	$ 10,264
Balance, Shares at Mar. 31, 2023		13,804