Consolidated Statements of Changes in Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Capital	Retained Earnings	Accumulated  Other Comprehensive Income	Treasury Stock
Beginning Balance, Shares at Dec. 31, 2022		5,173,000
Beginning Balance, value at Dec. 31, 2022	$ 236,499	$ 5,173	$ 33,865	$ 172,243	$ 25,586	$ (368)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	11,226			11,226
Dividends paid ($4.50 per common share)	(23,072)			(23,072)
Change in fair value of interest rate derivatives and other	(3,644)				(3,644)
Ending Balance, Shares at Mar. 31, 2023		5,173,000
Ending Balance, value at Mar. 31, 2023	$ 221,009	$ 5,173	33,865	160,397	21,942	(368)
Beginning Balance, Shares at Dec. 31, 2023	5,173,450	5,173,000
Beginning Balance, value at Dec. 31, 2023	$ 237,657	$ 5,173	34,315	182,336	16,201	(368)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	16,109			16,109
Dividends paid ($4.50 per common share)	(23,088)			(23,088)
Change in fair value of interest rate derivatives and other	$ (540)				(540)
Ending Balance, Shares at Mar. 31, 2024	5,173,450	5,173,000
Ending Balance, value at Mar. 31, 2024	$ 230,138	$ 5,173	$ 34,315	$ 175,357	$ 15,661	$ (368)