Long-Term Debt (Schedule of Long-term Debt) (Details) - USD ($) $ in Millions	Sep. 30, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Principal Amount	$ 4,916	$ 5,283
Unamortized Discount and Debt Issuance Costs	(97)	(103)
Net Long-term Debt	4,819	5,180
Net Long-term Debt, Current portion	(6)	(269)
Principal Amount, Long-term debt, net of current portion	4,910	5,014
Unamortized Discount and Debt Issuance Costs, Net of current portion	(97)	(103)
Long-term debt, net of current portion	$ 4,813	4,911
Senior Notes \| 3.60% Senior Notes Due 2022
Debt Instrument [Line Items]
Stated interest rate (percent)	3.60%
Principal Amount	$ 0	250
Unamortized Discount and Debt Issuance Costs	0	0
Net Long-term Debt	0	250
Principal Amount, Current portion	0	(250)
Unamortized Discount and Debt Issuance Costs, Current portion	0	0
Net Long-term Debt, Current portion	$ 0	(250)
Senior Notes \| 0.875% Senior Notes Due 2024
Debt Instrument [Line Items]
Stated interest rate (percent)	0.875%
Principal Amount	$ 300	300
Unamortized Discount and Debt Issuance Costs	(2)	(2)
Net Long-term Debt	$ 298	298
Senior Notes \| 3.6% Senior Notes Due 2026
Debt Instrument [Line Items]
Stated interest rate (percent)	3.60%
Principal Amount	$ 750	750
Unamortized Discount and Debt Issuance Costs	(4)	(5)
Net Long-term Debt	746	745
Senior Notes \| Loan related to tax-exempt waste disposal revenue bonds due 2027
Debt Instrument [Line Items]
Principal Amount	11	11
Unamortized Discount and Debt Issuance Costs	0	0
Net Long-term Debt	$ 11	11
Senior Notes \| 1.625% Senior Notes Due 2029
Debt Instrument [Line Items]
Stated interest rate (percent)	1.625%
Principal Amount	$ 686	794
Unamortized Discount and Debt Issuance Costs	(7)	(8)
Net Long-term Debt	$ 679	786
Senior Notes \| 3.375% Senior Notes Due 2030
Debt Instrument [Line Items]
Stated interest rate (percent)	3.375%
Principal Amount	$ 300	300
Unamortized Discount and Debt Issuance Costs	(3)	(4)
Net Long-term Debt	$ 297	296
Senior Notes \| 3.50% Senior Notes Due 2032
Debt Instrument [Line Items]
Stated interest rate (percent)	3.50%
Principal Amount	$ 250	250
Unamortized Discount and Debt Issuance Costs	(1)	(1)
Net Long-term Debt	$ 249	249
Senior Notes \| 2.875% Senior Notes Due 2041
Debt Instrument [Line Items]
Stated interest rate (percent)	2.875%
Principal Amount	$ 350	350
Unamortized Discount and Debt Issuance Costs	(11)	(11)
Net Long-term Debt	$ 339	339
Senior Notes \| 5.0% Senior Notes Due 2046
Debt Instrument [Line Items]
Stated interest rate (percent)	5.00%
Principal Amount	$ 700	700
Unamortized Discount and Debt Issuance Costs	(21)	(22)
Net Long-term Debt	$ 679	678
Senior Notes \| 4.375% Senior Notes Due 2047
Debt Instrument [Line Items]
Stated interest rate (percent)	4.375%
Principal Amount	$ 500	500
Unamortized Discount and Debt Issuance Costs	(8)	(8)
Net Long-term Debt	$ 492	492
Senior Notes \| 3.125% Senior Notes Due 2051
Debt Instrument [Line Items]
Stated interest rate (percent)	3.125%
Principal Amount	$ 600	600
Unamortized Discount and Debt Issuance Costs	(22)	(23)
Net Long-term Debt	$ 578	577
Senior Notes \| 3.375% 2061 Senior Notes
Debt Instrument [Line Items]
Stated interest rate (percent)	3.375%
Principal Amount	$ 450	450
Unamortized Discount and Debt Issuance Costs	(18)	(19)
Net Long-term Debt	$ 432	431
Senior Notes \| 8.73% Senior Notes Due 2022
Debt Instrument [Line Items]
Stated interest rate (percent)	8.73%
Principal Amount	$ 6	19
Unamortized Discount and Debt Issuance Costs	0	0
Net Long-term Debt	6	19
Principal Amount, Current portion	(6)	(19)
Unamortized Discount and Debt Issuance Costs, Current portion	0	0
Net Long-term Debt, Current portion	(6)	(19)
Senior Notes \| Term Loan Due 2026
Debt Instrument [Line Items]
Principal Amount	13	9
Unamortized Discount and Debt Issuance Costs	0	0
Net Long-term Debt	$ 13	$ 9

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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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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