CONDENSED STATEMENTS OF EARNINGS (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Revenues:
Total revenues	$ 666,809	$ 704,845	$ 2,182,472	$ 2,249,204
Costs and expenses:
Costs of sales and operating expenses	458,514	498,421	1,558,664	1,640,366
Selling, general and administrative	64,656	70,032	206,602	239,416
Taxes, other than on income	10,909	10,523	31,486	29,610
Depreciation and amortization	54,455	57,930	164,771	167,640
(Gain) loss on disposition of assets	374	(18)	(4,901)	(2,358)
Total costs and expenses	588,908	636,888	1,956,622	2,074,674
Operating income	77,901	67,957	225,850	174,530
Other income	864	1,454	2,677	4,586
Interest expense	(14,310)	(12,345)	(43,026)	(34,665)
Earnings before taxes on income	64,455	57,066	185,501	144,451
Provision for taxes on income	(16,305)	(15,116)	(45,454)	(41,042)
Net earnings	48,150	41,950	140,047	103,409
Less: Net earnings attributable to noncontrolling interests	(163)	(134)	(477)	(520)
Net earnings attributable to Kirby	$ 47,987	$ 41,816	$ 139,570	$ 102,889
Net earnings per share attributable to Kirby common stockholders:
Basic (in dollars per share)	$ 0.80	$ 0.70	$ 2.33	$ 1.72
Diluted (in dollars per share)	$ 0.80	$ 0.70	$ 2.32	$ 1.72
Marine Transportation [Member]
Revenues:
Total revenues	$ 412,665	$ 382,040	$ 1,185,072	$ 1,100,606
Distribution and Services [Member]
Revenues:
Total revenues	$ 254,144	$ 322,805	$ 997,400	$ 1,148,598