CONDENSED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Statement of Comprehensive Income [Abstract]
Net earnings	$ 94,378	$ 83,982	$ 170,648	$ 153,897
Other comprehensive income (loss), net of taxes:
Pension and postretirement benefits	(4,199)	986	(6,066)	591
Foreign currency translation adjustments	178	(473)	486	(473)
Total other comprehensive income (loss), net of taxes	(4,021)	513	(5,580)	118
Total comprehensive income, net of taxes	90,357	84,495	165,068	154,015
Net (earnings) loss attributable to noncontrolling interests	(101)	(128)	(385)	25
Comprehensive income attributable to Kirby	$ 90,256	$ 84,367	$ 164,683	$ 154,040

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.

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

+ References + Details

- Definition

Amount of Net Income (Loss) attributable to noncontrolling interest.

+ References

+ Details

- Definition

Amount after tax and reclassification adjustments of other comprehensive income (loss).

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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