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

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The effective interest rate at the end of the reporting period.

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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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Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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Long-Term Debt (Narrative) (Details) - USD ($) $ in Millions	Mar. 20, 2020	Mar. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Long-term Debt		$ 4,432	$ 3,445
Unamortized Debt Issuance Cost		$ 29	30
Senior Notes [Member] \| 1.625% Senior Notes Due 2029
Debt Instrument [Line Items]
Stated interest rate (percent)		1.625%
Long-term Debt		$ 760	774
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Interest Rate at Period End		2.25%
Revolving Credit Facility [Member] \| Line of Credit [Member] \| Credit Agreement [Member]
Debt Instrument [Line Items]
Proceeds from Lines of Credit	$ 1,000
Long-term Debt		$ 1,000	$ 0