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Long-Term Debt (Schedule Of Long-Term Debt) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020	Jul. 17, 2019	Nov. 30, 2017	Aug. 10, 2016	Jul. 31, 2012
Debt Instrument [Line Items]
Principal amount	$ 5,283	$ 3,620
Unamortized Premium (Discount) and Debt Issuance Costs	(103)	(54)
Long-term debt, net	5,180	3,566
Long-term Debt, Gross Excluding Current Maturities	5,014	3,620
Debt Instrument, Unamortized Premium (Discount) and Debt Issuance Cost, Net, Excluding Current Maturities	(103)	(54)
Long-term Debt, Excluding Current Maturities	4,911	3,566
Long-Term Debt, Maturity, Year One	269
Current portion of long-term debt, net	$ 269	0
Senior Notes \| 3.60% Senior Notes Due 2022
Debt Instrument [Line Items]
Stated interest rate (percent)	3.60%
Principal amount	$ 250	250				$ 250
Unamortized Premium (Discount) and Debt Issuance Costs	0	(1)
Long-term debt, net	250	249
Debt Instrument Unamortized Discount Premium and debt issuance cost net Current Maturities	0	0
Current portion of long-term debt, net	250	0
Long Term Debt Gross Current Maturities	$ (250)	0
Senior Notes \| 0.875% 2024 Senior Notes
Debt Instrument [Line Items]
Stated interest rate (percent)	0.875%
Principal amount	$ 300	0
Unamortized Premium (Discount) and Debt Issuance Costs	(2)	0
Long-term debt, net	$ 298	0
Senior Notes \| 3.60% Senior Notes Due 2026
Debt Instrument [Line Items]
Stated interest rate (percent)	3.60%
Principal amount	$ 750	750			$ 750
Unamortized Premium (Discount) and Debt Issuance Costs	(5)	(6)
Long-term debt, net	745	744
Senior Notes \| Loan related to tax-exempt waste disposal revenue bonds due 2027
Debt Instrument [Line Items]
Principal amount	11	11
Unamortized Premium (Discount) and Debt Issuance Costs	0	0
Long-term debt, net	$ 11	11
Senior Notes \| 1.625% Senior Notes Due 2029
Debt Instrument [Line Items]
Stated interest rate (percent)	1.625%
Principal amount	$ 794	859
Unamortized Premium (Discount) and Debt Issuance Costs	(8)	(10)
Long-term debt, net	$ 786	849	$ 779
Senior Notes \| 3.375 Senior Notes Due 2030
Debt Instrument [Line Items]
Stated interest rate (percent)	3.375%
Principal amount	$ 300	300
Unamortized Premium (Discount) and Debt Issuance Costs	(4)	(4)
Long-term debt, net	$ 296	296
Senior Notes \| 3.50% Senior Notes Due 2032
Debt Instrument [Line Items]
Stated interest rate (percent)	3.50%
Principal amount	$ 250	250
Unamortized Premium (Discount) and Debt Issuance Costs	(1)	(1)
Long-term debt, net	249	249
Senior Notes \| 6 1/2% GO Zone Senior Notes Due 2029 [Member]
Debt Instrument [Line Items]
Principal amount	600	0
Unamortized Premium (Discount) and Debt Issuance Costs	(23)	0
Senior Notes \| 6 1/2% GO Zone Senior Notes Due 2035 [Member]
Debt Instrument [Line Items]
Principal amount	350	0
Unamortized Premium (Discount) and Debt Issuance Costs	(11)	0
Senior Notes \| 6.5% 2035 IKE Zone Senior Notes [Member]
Debt Instrument [Line Items]
Principal amount	450	0
Unamortized Premium (Discount) and Debt Issuance Costs	$ (19)	0
Senior Notes \| 5.0% 2046 Senior Notes
Debt Instrument [Line Items]
Stated interest rate (percent)	5.00%
Principal amount	$ 700	700			$ 700
Unamortized Premium (Discount) and Debt Issuance Costs	(22)	(23)
Long-term debt, net	$ 678	677
Senior Notes \| 4.375% 2047 Senior Notes
Debt Instrument [Line Items]
Stated interest rate (percent)	4.375%
Principal amount	$ 500	500		$ 500
Unamortized Premium (Discount) and Debt Issuance Costs	(8)	(9)
Long-term debt, net	$ 492	491
Senior Notes \| 2.875% Senior Notes Due 2041
Debt Instrument [Line Items]
Stated interest rate (percent)	2.875%
Long-term debt, net	$ 339	0
Senior Notes \| 8.73% 2022 RS Cogen Debt
Debt Instrument [Line Items]
Stated interest rate (percent)	8.73%
Principal amount	$ 19	0
Unamortized Premium (Discount) and Debt Issuance Costs	0	0
Long-term debt, net	19	0
Debt Instrument Unamortized Discount Premium and debt issuance cost net Current Maturities	0	0
Current portion of long-term debt, net	19	0
Long Term Debt Gross Current Maturities	$ (19)	0
Senior Notes \| 3.375% 2061 Senior Notes
Debt Instrument [Line Items]
Stated interest rate (percent)	3.375%
Long-term debt, net	$ 431	0
Senior Notes \| 3.125% 2051 Senior Notes
Debt Instrument [Line Items]
Stated interest rate (percent)	3.125%
Long-term debt, net	$ 577	0
Senior Notes \| 2026 Term Loans
Debt Instrument [Line Items]
Stated interest rate (percent)	0.20%
Principal amount	$ 9	0
Unamortized Premium (Discount) and Debt Issuance Costs	0	0
Long-term debt, net	$ 9	$ 0