CONDENSED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
CONDENSED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) [Abstract]
Net earnings	$ 47,440	$ 28,793	$ 91,897	$ 61,459
Other comprehensive income (loss), net of taxes:
Pension and postretirement benefits	6,057	(13)	6,468	417
Foreign currency translation adjustments	(53)	(429)	76	(9)
Reclassification to retained earnings of stranded tax effects from tax reform	0	0	0	(7,925)
Total other comprehensive income (loss), net of taxes	6,004	(442)	6,544	(7,517)
Total comprehensive income, net of taxes	53,444	28,351	98,441	53,942
Net earnings attributable to noncontrolling interests	(153)	(191)	(314)	(386)
Comprehensive income attributable to Kirby	$ 53,291	$ 28,160	$ 98,127	$ 53,556

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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