CONDENSED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2013		Sep. 30, 2012		Sep. 30, 2013		Sep. 30, 2012
CONDENSED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) [Abstract]
Net earnings	$ 69,696		$ 53,731		$ 191,040		$ 154,045
Other comprehensive income (loss), net of taxes:
Pension and postretirement benefits	1,185		1,048		2,856		769
Foreign currency translation adjustments	(124)	[1]	(257)	[1]	125	[1]	190	[1]
Change in fair value of derivative instruments	(12)		1,331		958		3,831
Total comprehensive income (loss), net of taxes	1,049	[2]	2,122	[2]	3,939	[2]	4,790	[2]
Total comprehensive income, net of taxes	70,745		55,853		194,979		158,835
Net earnings attributable to noncontrolling interests	(573)		(676)		(2,246)		(2,495)
Comprehensive income attributable to Kirby	$ 70,172		$ 55,177		$ 192,733		$ 156,340

[1] Actuarial gains (losses) are amortized into costs of sales and operating expenses or selling, general and administrative expenses as appropriate.  (See Note 12 – Retirement Plans)

[2] Reclassifications to net earnings of derivatives qualifying as effective hedges are recognized in interest expense or costs of sales and operating expenses as appropriate.  (See Note 6 – Derivative Instruments)