Amount of short-term and long-term debt and lease obligation.

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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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Amount, after accumulated amortization, of debt premium.

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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.

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Date the credit facility terminates, in CCYY-MM-DD format.

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Date the credit facility first became available, in CCYY-MM-DD format.

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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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The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

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The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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Senior Long-Term Debt And Other Debt (Summary Of Senior Long-Term Debt And Other Debt) (Details) - USD ($) $ in Thousands		12 Months Ended
	Sep. 17, 2019	Dec. 31, 2019	Sep. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Line of credit facility, initiation date		Apr. 10, 2019
Line of credit facility, expiration date		Apr. 10, 2024
Senior long-term debt and other debt		$ 3,534,183		$ 3,009,577
7.125% Unsecured Senior Notes Due September 30, 2019 [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate		7.125%
6.25% Unsecured Senior Notes Due September 30, 2020 [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate			6.25%
5.35% Unsecured Senior Notes Due June 1, 2021 [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate			5.35%
3.35% Unsecured Senior Notes Due September 17 2029 [Member]
Debt Instrument [Line Items]
Proceeds from debt, net of issuance costs	$ 297,500
4.15% Unsecured Senior Notes Due September 17 2050 [Member]
Debt Instrument [Line Items]
Proceeds from debt, net of issuance costs	494,500
Unsecured Senior Notes [Member] \| 7.125% Unsecured Senior Notes Due September 30, 2019 [Member]
Debt Instrument [Line Items]
Unsecured senior notes		$ 0		$ 234,640
Debt instrument, interest rate		7.125%		7.125%
Debt instrument, unamortized discount		$ 0		$ 142
Unsecured Senior Notes [Member] \| 6.25% Unsecured Senior Notes Due September 30, 2020 [Member]
Debt Instrument [Line Items]
Unsecured senior notes		$ 0		$ 367,213
Debt instrument, interest rate		6.25%		6.25%
Debt Instrument, unamortized premium		$ 0		$ 17,213
Unsecured Senior Notes [Member] \| 5.35% Unsecured Senior Notes Due June 1, 2021 [Member]
Debt Instrument [Line Items]
Unsecured senior notes		$ 0		$ 249,417
Debt instrument, interest rate		5.35%		5.35%
Debt instrument, unamortized discount		$ 0		$ 499
Unsecured Senior Notes [Member] \| 4.90% Unsecured Senior Notes Due July 1, 2022 [Member]
Debt Instrument [Line Items]
Unsecured senior notes		$ 349,181		$ 348,864
Debt instrument, interest rate		4.90%		4.90%
Debt instrument, unamortized discount		$ 705		$ 978
Unsecured Senior Notes [Member] \| 3.625% Unsecured Senior Notes Due March 30, 2023 [Member]
Debt Instrument [Line Items]
Unsecured senior notes		$ 249,226		$ 248,988
Debt instrument, interest rate		3.625%		3.625%
Debt instrument, unamortized discount		$ 653		$ 855
Unsecured Senior Notes [Member] \| 3.50% Unsecured Senior Notes Due November 1, 2027 [Member]
Debt Instrument [Line Items]
Unsecured senior notes		$ 297,402		$ 297,035
Debt instrument, interest rate		3.50%		3.50%
Debt instrument, unamortized discount		$ 2,013		$ 2,298
Unsecured Senior Notes [Member] \| 3.35% Unsecured Senior Notes Due September 17 2029 [Member]
Debt Instrument [Line Items]
Debt instrument, face amount	$ 300,000
Unsecured senior notes		$ 297,125		$ 0
Debt instrument, interest rate	3.35%	3.35%		3.35%
Debt instrument, unamortized discount		$ 2,410		$ 0
Unsecured Senior Notes [Member] \| 7.35% Unsecured Senior Notes Due August 15, 2034 [Member]
Debt Instrument [Line Items]
Unsecured senior notes		$ 128,788		$ 128,715
Debt instrument, interest rate		7.35%		7.35%
Debt instrument, unamortized discount		$ 1,005		$ 1,074
Unsecured Senior Notes [Member] \| 5.0% Unsecured Senior Notes Due March 30, 2043 [Member]
Debt Instrument [Line Items]
Unsecured senior notes		$ 244,505		$ 244,269
Debt instrument, interest rate		5.00%		5.00%
Debt instrument, unamortized discount		$ 5,207		$ 5,431
Unsecured Senior Notes [Member] \| 5.0% Unsecured Senior Notes Due April 5, 2046 [Member]
Debt Instrument [Line Items]
Unsecured senior notes		$ 492,761		$ 492,486
Debt instrument, interest rate		5.00%		5.00%
Debt instrument, unamortized discount		$ 6,421		$ 6,664
Unsecured Senior Notes [Member] \| 4.30% Unsecured Senior Notes Due November 1, 2047 [Member]
Debt Instrument [Line Items]
Unsecured senior notes		$ 295,154		$ 294,975
Debt instrument, interest rate		4.30%		4.30%
Debt instrument, unamortized discount		$ 4,126		$ 4,278
Unsecured Senior Notes [Member] \| 5.0% Unsecured Senior Notes Due May 20, 2049 [Member] [Domain]
Debt Instrument [Line Items]
Unsecured senior notes		$ 591,010		$ 0
Debt instrument, interest rate		5.00%		5.00%
Debt instrument, unamortized discount		$ 7,684		$ 0
Unsecured Senior Notes [Member] \| 4.15% Unsecured Senior Notes Due September 17 2050 [Member]
Debt Instrument [Line Items]
Debt instrument, face amount	$ 500,000
Unsecured senior notes		$ 493,759		$ 0
Debt instrument, interest rate	4.15%	4.15%		4.15%
Debt instrument, unamortized discount		$ 5,449		$ 0
Other Debt [Member]
Debt Instrument [Line Items]
Senior long-term debt and other debt		$ 95,272		102,975
Other Debt [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate		1.70%
Other Debt [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate		6.10%
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity		$ 300,000		300,000
Long-term line of credit		$ 0		$ 0
Line of credit facility, unused capacity, commitment fee percentag		0.20%
Secured Letters Of Credit [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity		$ 200,000