CONSOLIDATED STATEMENTS OF EARNINGS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Revenues:
Revenues	$ 3,364,050	$ 3,265,876	$ 3,091,640
Costs and expenses:
Costs of sales and operating expenses	2,216,501	2,200,354	2,180,422
Selling, general and administrative	356,305	337,097	335,213
Taxes, other than on income	35,622	34,910	34,766
Depreciation and amortization	264,126	240,322	211,156
Impairments	0	56,303	0
Gain on disposition of assets	(4,788)	(2,207)	(5,009)
Total costs and expenses	2,867,766	2,866,779	2,756,548
Operating income	496,284	399,097	335,092
Other income	21,455	12,795	11,041
Interest expense	(46,327)	(49,129)	(52,008)
Earnings before taxes on income	471,412	362,763	294,125
Provision for taxes on income	(115,997)	(75,867)	(71,220)
Net earnings	355,415	286,896	222,905
Less: Net (earnings) loss attributable to noncontrolling interests	(846)	(189)	30
Net earnings attributable to Kirby	$ 354,569	$ 286,707	$ 222,935
Net earnings per share attributable to Kirby common stockholders:
Basic	$ 6.37	$ 4.95	$ 3.74
Diluted	$ 6.33	$ 4.91	$ 3.72
Marine Transportation [Member]
Revenues:
Revenues	$ 1,935,305	$ 1,913,050	$ 1,721,937
Distribution and Services [Member]
Revenues:
Revenues	$ 1,428,745	$ 1,352,826	$ 1,369,703