Debt And Related Expenses (Narrative) (Details) $ in Millions	9 Months Ended
Sep. 30, 2021 USD ($)
Debt Instrument [Line Items]
Repayments of long-term debt	$ 1,243
Early retirement of debt	30
Charge on early retirement of debt, cash retirement costs	59
Senior Credit Facility [Member]
Debt Instrument [Line Items]
Credit Facility, borrowing capacity	3,000
Outstanding credit facility borrowings	$ 0
Debt-to-capitalization ratio	0.65
Outstanding letters of credit	$ 2
Senior Credit Facility [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt-to-capitalization ratio	0.251
Senior Notes [Member]
Debt Instrument [Line Items]
Early retirement of debt	$ 30
Charge on early retirement of debt, cash retirement costs	59
Charge on early retirement of debt, noncash charges	89
6.00% Due 2022 [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Repayments of long-term debt	$ 43
Debt interest rate, stated percentage	6.00%
5.875% Due 2028 [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Repayments of long-term debt	$ 175
Debt interest rate, stated percentage	5.875%
4.5% Due 2030 [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Repayments of long-term debt	$ 315
Debt interest rate, stated percentage	4.50%
5.25% Due 2027 [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Repayments of long-term debt	$ 210
Debt interest rate, stated percentage	5.25%
5.75% due June 1, 2026 [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Repayments of long-term debt	$ 500
Debt interest rate, stated percentage	5.75%

Noncash gain (loss) on extinguishment of debt.

No definition available.

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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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

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

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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.

+ References

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- Definition

Amount of cash outflow for cost from early extinguishment and prepayment of debt. Includes, but is not limited to, third-party cost, premium paid, and other fee paid to lender directly for debt extinguishment or debt prepayment. Excludes accrued interest.

+ References

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- Definition

Indebtedness divided by net capital.

+ References

No definition available.

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- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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