Long-Term Debt (2026 Term Loans) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Debt Disclosure [Abstract]
Long-term Debt	$ 5,180	$ 3,566
2026 Term Loans \| Senior Notes
Debt Disclosure [Abstract]
Long-term Debt	$ 9	$ 0
Debt Instrument [Line Items]
Stated interest rate (percent)	0.20%
Taiwan Chlorine Industries, Ltd. \| 2026 Term Loans \| Senior Notes
Debt Disclosure [Abstract]
Ownership percentage by parent	60.00%
Debt Instrument [Line Items]
Ownership percentage by parent	60.00%
Line of Credit Facility, Maximum Borrowing Capacity	$ 22

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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