ENVIRONMENTAL LIABILITIES AND EXPENDITURES - Narrative (Details)	1 Months Ended					3 Months Ended	12 Months Ended
	Jan. 31, 2025 USD ($)	Jan. 31, 2024 company	Sep. 30, 2021 USD ($) mi	Jun. 30, 2018 USD ($)	Mar. 31, 2016 mi	Dec. 31, 2024 USD ($) site	Dec. 31, 2025 USD ($) site segment	Dec. 31, 2024 USD ($) site	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($) party
Environmental remediation reserves
Percent of reserve to be funded over the next three to four years							30.00%
Minimum period of expending second half of environmental reserves							10 years
Number of sites | site						158	152	158
Remediation balance						$ 1,909,000,000	$ 1,870,000,000	$ 1,909,000,000
Environmental reserves, exceeding $ ten million, threshold value							$ 10,000,000
Environmental reserves, exceeding $ ten million, threshold value, number of sites | site							14
Environmental reserves, range between zero to $ one million site category, number of sites | site							88
Environmental costs recognized, capitalized in period							$ 196,000,000
Environmental remediation additional loss range							1,900,000,000
Continuing operations
Environmental remediation reserves
Environmental remediation expense							18,000,000	20,000,000	$ 46,000,000
Remediation balance						225,000,000	196,000,000	225,000,000
Discontinued Operations
Environmental remediation reserves
Environmental remediation expense							$ 64,000,000	56,000,000	$ 33,000,000
Environmental remediation expense statement of income or comprehensive income, not disclosed							64 million
Remediation balance						$ 1,684,000,000	$ 1,674,000,000	$ 1,684,000,000
Low end of range
Environmental remediation reserves
Period of expending 40 percent of environmental reserves							3 years
High end of range
Environmental remediation reserves
Period of expending 40 percent of environmental reserves							4 years
Environmental reserves, range between zero to $ one million site category							$ 1,000,000
Non-National Priorities List Sites
Environmental remediation reserves
Environmental remediation contingency, number of site categories | site							3
NPL Sites
Environmental remediation reserves
Number of sites | site						32	29	32
Remediation balance						$ 1,374,000,000	$ 1,379,000,000	$ 1,374,000,000
Third-Party Sites
Environmental remediation reserves
Number of sites | site						63	69	63
Remediation balance						$ 200,000,000	$ 238,000,000	$ 200,000,000
Number of sites with significant environmental remediation reserves | site							8
Currently Operated Sites
Environmental remediation reserves
Number of sites | site						12	4	12
Remediation balance						$ 88,000,000	$ 25,000,000	$ 88,000,000
Number of sites with significant environmental remediation reserves | site							1
Closed or Non-Operated Sites
Environmental remediation reserves
Number of sites | site						51	50	51
Remediation balance						$ 247,000,000	$ 228,000,000	$ 247,000,000
Closed or Non-Operated Sites | Western New York, Oklahoma, California, New York, Pennsylvania
Environmental remediation reserves
Number of sites | site							7
Diamond Alkali Superfund Site
Environmental remediation reserves
Site contingency, number of operating units | segment							4
Diamond Alkali Superfund Site - Operable Unit One
Environmental remediation reserves
Environmental remediation expense	$ 16,000,000
Diamond Alkali Superfund Site - Operable Unit Two
Environmental remediation reserves
Environmental remediation expense				$ 1,400,000,000
Stretch of lower passaic river requiring remedial actions | mi					8.3
Diamond Alkali Superfund Site - Operable Unit Four
Environmental remediation reserves
Environmental remediation expense			$ 440,000,000
Stretch of lower passaic river requiring remedial actions | mi			17
Stretch of lower passaic river not covered by remedial actions | mi			9
Alden Leeds | Alden Leeds
Environmental remediation reserves
Environmental remediation expense										$ 150,000,000
Number of parties, settled | party										85
Number of companies excluded from settlement | company		3
Clean up costs percentage							85.00%	85.00%
Increase in environmental remediation liability						$ 925,000,000
Alden Leeds | Low end of range | Alden Leeds
Environmental remediation reserves
Remediation costs, period							10 years
Alden Leeds | High end of range | Alden Leeds
Environmental remediation reserves
Remediation costs, period							20 years