Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Statement of Comprehensive Income [Abstract]
Net income (loss) attributable to Union Carbide Corporation	$ 782	$ (26)	$ 660	$ 204
Cumulative translation adjustments	(1)	(1)	(2)	(1)
Pension and other postretirement benefit plans	12	11	33	31
Total other comprehensive income	11	10	31	30
Comprehensive income attributable to Union Carbide Corporation	$ 793	$ (16)	$ 691	$ 234

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.

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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+ Details

- Definition

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

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