Debt (Debt Exchange) (Narrative) (Details) $ in Millions	Apr. 06, 2021 USD ($)
Debt Conversion [Line Items]
Original debt	$ 1,700
Date of exchange	Apr. 06, 2021
Cash consideration	$ 257
Accrued and unpaid interest	14
Debt exchange fees	$ 12
Minimum [Member]
Debt Conversion [Line Items]
Original due date year	2028
Maximum [Member]
Debt Conversion [Line Items]
Original due date year	2065
2.891% Notes Due 2036 [Member]
Debt Conversion [Line Items]
New debt	$ 701
New rate	2.891%
New due date	Apr. 06, 2036
3.799% Notes Due 2071 [Member]
Debt Conversion [Line Items]
New debt	$ 1,000
New rate	3.799%
New due date	Apr. 06, 2071

Accrued interest paid to debt holder on the existing debt at date of exchange.

No definition available.

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- Definition

The value of the financial instrument(s) that the original debt is being converted into in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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- Definition

Expiration, mandatory redemption, or due date, in CCYY-MM-DD format, of the financial instrument issued in exchange for the original debt being converted in a noncash or part noncash transaction.

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- Definition

Date the financial instrument was issued in exchange for the original debt being converted in a noncash or part noncash transaction, in CCYY-MM-DD format.

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- Definition

Dividend or interest rate associated with the financial instrument issued in exchange for the original debt being converted in a noncash or part noncash transaction. Noncash are transactions that affect recognized assets or liabilities but that do not result in cash receipts or cash payments. Part noncash refers to that portion of the transaction not resulting in cash receipts or cash payments.

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- Definition

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.

+ References

No definition available.

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- Definition

The amount of the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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- Definition

Year the original debt was scheduled to mature, in CCYY format.

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- Definition

The amount of debt issuance costs that were incurred during a noncash or partial noncash transaction.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
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- Definition

The total of the cash outflow during the period which has been paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt and the cost incurred directly for the issuance of equity securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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