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

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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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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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Amount of cash paid for interest, including, but not limited to, capitalized interest and payment to settle zero-coupon bond attributable to accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount; classified as operating and investing activities.

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- Definition

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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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Debt (Narrative) (Details) - USD ($)	1 Months Ended	12 Months Ended
Debt (Narrative) (Details) - USD ($)	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jul. 01, 2018
Debt Instrument [Line Items]
Repayments of debt	$ 2,500,000,000
Interest payments		$ 459,000,000	$ 434,000,000	$ 312,000,000
Credit facility, maximum borrowing capacity		5,000,000,000
Commercial Paper
Debt Instrument [Line Items]
Commercial paper outstanding		0
Credit Facility \| 364-day Committed Bank Credit Facility due March 2021
Debt Instrument [Line Items]
Credit facility, maximum borrowing capacity		$ 2,000,000,000
Debt instrument term		364 days
Credit Facility \| Multi Year Facility Expiring March 2023
Debt Instrument [Line Items]
Credit facility, maximum borrowing capacity		$ 2,000,000,000
Credit Facility \| Multi-year Facility Expiring March 2025
Debt Instrument [Line Items]
Credit facility, maximum borrowing capacity		$ 1,000,000,000
Notes
Debt Instrument [Line Items]
Debt issued	$ 4,000,000,000				$ 7,500,000,000