Long-Term Debt And Borrowing Arrangements (Schedule Of Long-Term Debt) (Detail Section) - USD ($)	3 Months Ended
Sep. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 1,200,000,000
Floating Rate Term Loan Due March Two Thousand Nineteen [Member]
Debt Instrument [Line Items]
Debt Instrument, Description of Variable Rate Basis	250 basis points
Long Term Borrowings [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	5.75%
Long Term Borrowings [Member] \| Five And One Over Two Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	5.50%
Long Term Borrowings [Member] \| Six And Three Over Eight Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	6.375%
Long Term Borrowings [Member] \| Five And One Over Four Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	5.25%
Long Term Borrowings [Member] \| Ten And One Over Two Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	1.05%
Senior Notes [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross		$ 336,000,000
Senior Notes [Member] \| Five And One Over Two Senior Notes [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 0	200,000,000
Debt Instrument, Face Amount	100,000,000
Senior Notes [Member] \| Six And Three Over Eight Senior Notes [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	350,000,000	350,000,000
Senior Notes [Member] \| Five And One Over Four Senior Notes [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	375,000,000	375,000,000
Senior Notes [Member] \| Floating Rate Term Loan Due February Two Thousand Twenty Seven [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	1,200,000,000
Senior Notes [Member] \| Ten And One Over Two Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	500,000,000
Loans Payable [Member] \| Floating Rate Term Loan Due February Two Thousand Twenty Seven [Member]
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 1,201,000,000	$ 1,112,000,000
Debt Instrument, Description of Variable Rate Basis	225 basis points
Percentage Of Margin Aggregate Interest Rate	2.43%
Debt Instrument, Basis Spread on Variable Rate	3.92%
Derivative, Amount of Hedged Item	$ 700,000,000

Percentage Of Margin Aggregate Interest Rate.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=120520924&loc=SL6031897-161870

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

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- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

+ Details

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28551-108399

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-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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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

Amount of hedged item in hedging relationship. Excludes hedged asset or liability.

+ References

No definition available.

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