Long-Term Debt (2026 Term Loans) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Long-term debt, principal amount	$ 4,997	$ 4,976
Weighted average interest rate	3.20%
Unamortized debt issuance costs	$ 36	40
Long-term debt, maturity, year one	300
Long-term debt, maturity, year three	763
Long-term debt, maturity, year four	$ 11
Term Loan Due 2026 \| Senior Notes
Debt Instrument [Line Items]
Loan term	5 years
Maximum borrowing capacity	$ 22
Stated interest rate (percent)	0.95%
Long-term debt, principal amount	$ 13	$ 15
Taiwan Chlorine Industries, Ltd. \| Term Loan Due 2026 \| Senior Notes
Debt Instrument [Line Items]
Ownership percentage by parent	60.00%

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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