Year when debt instrument is scheduled to be fully repaid.

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Face (par) amount of debt instrument at time of issuance.

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

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount, after accumulated amortization, of debt discount.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of long-term debt and lease obligation, classified as noncurrent.

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Amount of long-term debt and lease obligation, classified as current.

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Amount of long-term debt and lease obligation, including portion classified as current.

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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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Debt, Long-term debt (Details) € in Millions, $ in Millions	1 Months Ended	6 Months Ended
Debt, Long-term debt (Details) € in Millions, $ in Millions	Apr. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2020 EUR (€)	Dec. 31, 2019 USD ($)
Long-term debt [Line Items]
Long-term debt		$ 13,677		$ 11,617
Current maturities of long-term debt		(3)		(3)
Long-term debt, non-current portion		$ 13,674		11,614
Senior Notes due 2021, $1,000 million, 6.0% ($3 million of debt issuance cost)
Long-term debt [Line Items]
Maturity year		2021
Face amount		$ 1,000
Stated interest rate (in hundredths)		6.00%	6.00%
Unamortized debt issuance cost		$ 3
Long-term debt		$ 1,012		998
Senior Notes due 2024, $1,000 million, 5.75% ($5 million of debt issuance cost)
Long-term debt [Line Items]
Maturity year		2024
Face amount		$ 1,000
Stated interest rate (in hundredths)		5.75%	5.75%
Unamortized debt issuance cost		$ 5
Long-term debt		$ 995		995
Senior Notes due 2055, $1,000 million, 4.625% ($16 million of discount; $11 million of debt issuance cost)
Long-term debt [Line Items]
Maturity year		2055
Face amount		$ 1,000
Stated interest rate (in hundredths)		4.625%	4.625%
Unamortized discount		$ 16
Unamortized debt issuance cost		11
Long-term debt		$ 973		973
Term Loan due 2022, $4,000 million ($2 million of debt issuance costs)
Long-term debt [Line Items]
Maturity year		2022
Maximum borrowing capacity		$ 4,000
Unamortized debt issuance cost		2
Long-term debt		$ 1,948		1,950
Guaranteed Notes due 2022, €750 million, 1.875% ($1 million of discount; $2 million of debt issuance cost)
Long-term debt [Line Items]
Maturity year		2022
Face amount \| €			€ 750
Stated interest rate (in hundredths)		1.875%	1.875%
Unamortized discount		$ 1
Unamortized debt issuance cost		2
Long-term debt		$ 839		841
Guaranteed Notes due 2023, $750 million, 4.0% ($4 million of discount; $2 million of debt issuance cost)
Long-term debt [Line Items]
Maturity year		2023
Face amount		$ 750
Stated interest rate (in hundredths)		4.00%	4.00%
Unamortized discount		$ 4
Unamortized debt issuance cost		2
Long-term debt		$ 744		744
Guaranteed Notes due 2025, $500 million, 2.875% ($4 million of debt issuance cost)
Long-term debt [Line Items]
Maturity year	2025	2025
Face amount	$ 500	$ 500
Stated interest rate (in hundredths)	2.875%	2.875%	2.875%
Unamortized debt issuance cost		$ 4
Long-term debt		$ 496
Guaranteed Notes due 2026, €500 million, 0.875% ($2 million of discount; $3 million of debt issuance cost)
Long-term debt [Line Items]
Maturity year		2026
Face amount \| €			€ 500
Stated interest rate (in hundredths)		0.875%	0.875%
Unamortized discount		$ 2
Unamortized debt issuance cost		3
Long-term debt		$ 556		555
Guaranteed Notes due 2027, $1,000 million, 3.5% ($7 million of discount; $6 million of debt issuance cost)
Long-term debt [Line Items]
Maturity year		2027
Face amount		$ 1,000
Stated interest rate (in hundredths)		3.50%	3.50%
Unamortized discount		$ 7
Unamortized debt issuance cost		6
Long-term debt		$ 1,097		1,023
Guaranteed Notes due 2027, $300 million, 8.1%
Long-term debt [Line Items]
Maturity year		2027
Face amount		$ 300
Stated interest rate (in hundredths)		8.10%	8.10%
Long-term debt		$ 300		300
Guaranteed Notes due 2030, $500 million, 3.375% ($1 million of discount; $4 million of debt issuance cost)
Long-term debt [Line Items]
Maturity year	2030	2030
Face amount	$ 500	$ 500
Stated interest rate (in hundredths)	3.375%	3.375%	3.375%
Unamortized discount		$ 1
Unamortized debt issuance cost		4
Long-term debt		$ 495
Guaranteed Notes due 2031, €500 million, 1.625% ($6 million of discount; $3 million of debt issuance cost)
Long-term debt [Line Items]
Maturity year		2031
Face amount \| €			€ 500
Stated interest rate (in hundredths)		1.625%	1.625%
Unamortized discount		$ 6
Unamortized debt issuance cost		3
Long-term debt		$ 551		552
Guaranteed Notes due 2043, $750 million, 5.25% ($20 million of discount; $7 million of debt issuance cost)
Long-term debt [Line Items]
Maturity year		2043
Face amount		$ 750
Stated interest rate (in hundredths)		5.25%	5.25%
Unamortized discount		$ 20
Unamortized debt issuance cost		7
Long-term debt		$ 723		723
Guaranteed Notes due 2044, $1,000 million, 4.875% ($10 million of discount; $9 million of debt issuance cost)
Long-term debt [Line Items]
Maturity year		2044
Face amount		$ 1,000
Stated interest rate (in hundredths)		4.875%	4.875%
Unamortized discount		$ 10
Unamortized debt issuance cost		9
Long-term debt		$ 981		980
Guaranteed Notes due 2049, $1,000 million, 4.2% ($15 million of discount; $10 million of debt issuance cost)
Long-term debt [Line Items]
Maturity year		2049
Face amount		$ 1,000
Stated interest rate (in hundredths)		4.20%	4.20%
Unamortized discount		$ 15
Unamortized debt issuance cost		10
Long-term debt		$ 975		975
Guaranteed Notes due 2050, $1,000 million, 4.2% ($6 million of discount; $10 million of debt issuance cost)
Long-term debt [Line Items]
Maturity year	2050	2050
Face amount	$ 1,000	$ 1,000
Stated interest rate (in hundredths)	4.20%	4.20%	4.20%
Unamortized discount		$ 6
Unamortized debt issuance cost		10
Long-term debt		984
Other long-term debt [Member]
Long-term debt [Line Items]
Long-term debt		$ 8		$ 8