Segment Data (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024 USD ($)	Jun. 30, 2023 USD ($)	Jun. 30, 2024 USD ($) Segment	Jun. 30, 2023 USD ($)	Dec. 31, 2023 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | Segment			2
Revenues [Abstract]
Revenues	$ 824,390	$ 777,248	$ 1,632,412	$ 1,527,692
Earnings before taxes on income	110,767	76,278	202,408	130,950
Total assets	5,865,898		5,865,898		$ 5,722,197
Other segment disclosures [Abstract]
Gain on disposition of assets	515	472	589	2,702
Interest expense	(12,819)	(12,286)	(25,970)	(25,507)
Earnings before taxes on income	110,767	76,278	202,408	130,950
Marine Transportation (KMT) [Member]
Revenues [Abstract]
Revenues	484,808	426,962	960,220	839,457
Distribution and Services [Member]
Revenues [Abstract]
Revenues	339,582	350,286	672,192	688,235
Other [Member]
Revenues [Abstract]
Earnings before taxes on income	(13,545)	(17,815)	(26,901)	(28,971)
Total assets	129,342		129,342		110,882
Other segment disclosures [Abstract]
General corporate expenses	(4,329)	(7,265)	(7,877)	(13,873)
Gain on disposition of assets	515	472	589	2,702
Interest expense	(12,819)	(12,286)	(25,970)	(25,507)
Other income	3,088	1,264	6,357	7,707
Earnings before taxes on income	(13,545)	(17,815)	(26,901)	(28,971)
Details of "Other" total assets [Abstract]
General corporate assets	126,949		126,949		108,306
Investment in affiliates	2,393		2,393		2,576
Total other assets	129,342		129,342		110,882
Reporting Segments [Member] | Marine Transportation (KMT) [Member]
Revenues [Abstract]
Revenues	484,808	426,962	960,220	839,457
Earnings before taxes on income	94,876	64,251	177,859	107,287
Total assets	4,557,755		4,557,755		4,454,931
Other segment disclosures [Abstract]
Earnings before taxes on income	94,876	64,251	177,859	107,287
Reporting Segments [Member] | Distribution and Services [Member]
Revenues [Abstract]
Revenues	339,582	350,286	672,192	688,235
Earnings before taxes on income	29,436	29,842	51,450	52,634
Total assets	1,178,801		1,178,801		$ 1,156,384
Other segment disclosures [Abstract]
Earnings before taxes on income	29,436	29,842	51,450	52,634
Intersegment Eliminations [Member]
Revenues [Abstract]
Revenues	7,500	10,300	14,100	19,700
Earnings before taxes on income	700	1,000	1,400	2,000
Other segment disclosures [Abstract]
Earnings before taxes on income	$ 700	$ 1,000	$ 1,400	$ 2,000