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Long-Term Debt (2026 Term Loans) (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021	Jul. 17, 2019
Debt Instrument [Line Items]
Long-term Debt	$ 4,879	$ 5,180
Long-term Debt, Weighted Average Interest Rate, at Point in Time	3.20%
Unamortized Debt Issuance Expense	$ 40	42
Long-Term Debt, Maturity, Year Two	300
Long-Term Debt, Maturity, Year Four	765
Long-Term Debt, Maturity, Year Five	$ 11
2026 Term Loans \| Senior Notes
Debt Instrument [Line Items]
Stated interest rate (percent)	0.20%
Long-term Debt	$ 15	9
0.875% 2024 Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Stated interest rate (percent)	0.875%
Long-term Debt	$ 299	298
3.60% Senior Notes Due 2026 \| Senior Notes
Debt Instrument [Line Items]
Stated interest rate (percent)	3.60%
Long-term Debt	$ 746	745
1.625% Senior Notes Due 2029 \| Senior Notes
Debt Instrument [Line Items]
Stated interest rate (percent)	1.625%
Long-term Debt	$ 743	786	$ 779
3.375 Senior Notes Due 2030 \| Senior Notes
Debt Instrument [Line Items]
Stated interest rate (percent)	3.375%
Long-term Debt	$ 297	296
3.50% Senior Notes Due 2032 \| Senior Notes
Debt Instrument [Line Items]
Stated interest rate (percent)	3.50%
Long-term Debt	$ 249	249
2.875% Senior Notes Due 2041 \| Senior Notes
Debt Instrument [Line Items]
Stated interest rate (percent)	2.875%
Long-term Debt	$ 339	339
5.00% 2046 Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Stated interest rate (percent)	5.00%
Long-term Debt	$ 679	678
4.375% 2047 Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Stated interest rate (percent)	4.375%
Long-term Debt	$ 492	492
3.125% 2051 Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Stated interest rate (percent)	3.125%
Long-term Debt	$ 578	577
3.375% 2061 Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Stated interest rate (percent)	3.375%
Long-term Debt	$ 431	$ 431
Taiwan Chlorine Industries, Ltd. \| 2026 Term Loans \| Senior Notes
Debt Instrument [Line Items]
Ownership percentage by parent	60.00%
Line of Credit Facility, Maximum Borrowing Capacity	$ 22