CONDENSED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
CONDENSED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) [Abstract]
Net earnings	$ 48,150	$ 41,950	$ 140,047	$ 103,409
Other comprehensive income (loss), net of taxes:
Pension and postretirement benefits	172	438	6,640	855
Foreign currency translation adjustments	(618)	(60)	(542)	(69)
Reclassification to retained earnings of stranded tax effects from tax reform	0	0	0	(7,925)
Total other comprehensive income (loss), net of taxes	(446)	378	6,098	(7,139)
Total comprehensive income, net of taxes	47,704	42,328	146,145	96,270
Net earnings attributable to noncontrolling interests	(163)	(134)	(477)	(520)
Comprehensive income attributable to Kirby	$ 47,541	$ 42,194	$ 145,668	$ 95,750

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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