Long-Term Debt (Schedule of Long-term Debt) (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Principal Amount	$ 5,267	$ 5,283
Unamortized Discount and Debt Issuance Costs	(101)	(103)
Net Long-term Debt	5,166	5,180
Long-term Debt, Current Maturities	(264)	(269)
Debt Instrument Unamortized Discount Premium and Debt Issuance Cost Net Excluding Current Maturities	(101)	(103)
Long term Debt Gross Excluding Current Maturities	5,003	5,014
Long-term debt, net of current portion	$ 4,902	4,911
Senior Notes \| 3.60% Senior Notes Due 2022
Debt Instrument [Line Items]
Stated interest rate (percent)	3.60%
Principal Amount	$ 250	250
Unamortized Discount and Debt Issuance Costs	0	0
Net Long-term Debt	250	250
Debt Instrument Unamortized Discount Premium and debt issuance cost net Current Maturities	0	0
Long Term Debt Gross Current Maturities	(250)	(250)
Long-term Debt, Current Maturities	$ (250)	(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	(5)	(5)
Net Long-term Debt	745	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	$ 778	794
Unamortized Discount and Debt Issuance Costs	(8)	(8)
Net Long-term Debt	$ 770	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	(23)	(23)
Net Long-term Debt	$ 577	577
Senior Notes \| 3.75% Senior Notes Due 2061
Debt Instrument [Line Items]
Stated interest rate (percent)	3.375%
Principal Amount	$ 450	450
Unamortized Discount and Debt Issuance Costs	(19)	(19)
Net Long-term Debt	$ 431	431
Senior Notes \| 8.73% Senior Notes Due 2022
Debt Instrument [Line Items]
Stated interest rate (percent)	8.73%
Principal Amount	$ 14	19
Unamortized Discount and Debt Issuance Costs	0	0
Net Long-term Debt	14	19
Debt Instrument Unamortized Discount Premium and debt issuance cost net Current Maturities	0	0
Long Term Debt Gross Current Maturities	(14)	(19)
Long-term Debt, Current Maturities	(14)	(19)
Senior Notes \| Term Loan Due 2026
Debt Instrument [Line Items]
Principal Amount	14	9
Unamortized Discount and Debt Issuance Costs	0	0
Net Long-term Debt	$ 14	$ 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, 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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