CONDENSED STATEMENTS OF EARNINGS - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Revenues:
Revenues	$ 764,772	$ 745,843	$ 2,292,464	$ 2,054,589
Costs and expenses:
Costs of sales and operating expenses	530,541	552,392	1,618,690	1,526,872
Selling, general and administrative	79,125	75,381	250,870	221,721
Taxes, other than on income	9,666	9,121	28,610	28,332
Depreciation and amortization	53,445	50,419	156,251	150,498
Gain on disposition of assets	(1,528)	(377)	(4,230)	(7,971)
Total costs and expenses	671,249	686,936	2,050,191	1,919,452
Operating income	93,523	58,907	242,273	135,137
Other income	1,589	3,805	9,296	11,853
Interest expense	(13,386)	(11,755)	(38,893)	(32,598)
Earnings before taxes on income	81,726	50,957	212,676	114,392
Provision for taxes on income	(18,722)	(11,713)	(51,733)	(28,956)
Net earnings	63,004	39,244	160,943	85,436
Net (earnings) loss attributable to noncontrolling interests	(40)	(153)	86	(454)
Net earnings attributable to Kirby	$ 62,964	$ 39,091	$ 161,029	$ 84,982
Net earnings per share attributable to Kirby common stockholders:
Basic	$ 1.06	$ 0.65	$ 2.7	$ 1.41
Diluted	$ 1.05	$ 0.65	$ 2.68	$ 1.41
Marine Transportation [Member]
Revenues:
Revenues	$ 429,885	$ 433,040	$ 1,269,342	$ 1,194,231
Distribution and Services [Member]
Revenues:
Revenues	$ 334,887	$ 312,803	$ 1,023,122	$ 860,358