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, 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, net	75		75
Issued, net (in shares)		19
Restricted stock-based compensation expense	376		376
Dividends and dividend equivalents	(19,820)				(19,820)
Comprehensive income:
Net income	7,935			7,935
Unrealized net gain/(loss) on cash flow hedges	(1,032)					(1,032)
Subtotal - comprehensive income	6,903			7,935		(1,032)
Balance at Jun. 30, 2023	216,635	$ 138	269,923	818,596	(883,001)	10,979
Balance, Shares at Jun. 30, 2023		13,822
Balance at Mar. 31, 2023	222,170	$ 138	269,698	815,120	(873,050)	10,264
Balance, Shares at Mar. 31, 2023		13,804
Shares of Beneficial Interest:
Issued, net	37		37
Issued, net (in shares)		18
Restricted stock-based compensation expense	188		188
Dividends and dividend equivalents	(9,951)				(9,951)
Comprehensive income:
Net income	3,476			3,476
Unrealized net gain/(loss) on cash flow hedges	715					715
Subtotal - comprehensive income	4,191			3,476		715
Balance at Jun. 30, 2023	216,635	$ 138	269,923	818,596	(883,001)	10,979
Balance, Shares at Jun. 30, 2023		13,822
Balance at Dec. 31, 2023	200,934	$ 138	270,398	826,061	(902,975)	7,312
Balance, Shares at Dec. 31, 2023		13,824
Shares of Beneficial Interest:
Issued, net	(207)		(207)
Issued, net (in shares)		26
Repurchased	(12)		(12)
Repurchased (in shares)		(1)
Restricted stock-based compensation expense	413		413
Dividends and dividend equivalents	(20,132)				(20,132)
Comprehensive income:
Net income	10,576			10,576
Unrealized net gain/(loss) on cash flow hedges	(871)					(871)
Subtotal - comprehensive income	9,705			10,576		(871)
Balance at Jun. 30, 2024	190,701	$ 138	270,592	836,637	(923,107)	6,441
Balance, Shares at Jun. 30, 2024		13,849
Balance at Mar. 31, 2024	196,458	$ 138	270,454	831,361	(912,998)	7,503
Balance, Shares at Mar. 31, 2024		13,825
Shares of Beneficial Interest:
Issued, net	(61)		(61)
Issued, net (in shares)		25
Repurchased	(12)		(12)
Repurchased (in shares)		(1)
Restricted stock-based compensation expense	211		211
Dividends and dividend equivalents	(10,109)				(10,109)
Comprehensive income:
Net income	5,276			5,276
Unrealized net gain/(loss) on cash flow hedges	(1,062)					(1,062)
Subtotal - comprehensive income	4,214			5,276		(1,062)
Balance at Jun. 30, 2024	$ 190,701	$ 138	$ 270,592	$ 836,637	$ (923,107)	$ 6,441
Balance, Shares at Jun. 30, 2024		13,849