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Senior Long-Term Debt And Other Debt (Summary Of Senior Long-Term Debt And Other Debt) (Details) - USD ($) $ in Thousands | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Debt Instrument [Line Items] |  |
Senior long-term debt and other debt | $ 3,779,796 | $ 4,103,629
Revolving Credit Facility [Member] |  |
Debt Instrument [Line Items] |  |
Borrowings outstanding under the facility | 0 | 0
Unsecured Senior Notes [Member] |  |
Debt Instrument [Line Items] |  |
Senior long-term debt and other debt | 3,439,199 |
Unsecured Senior Notes [Member] | 3.625% Unsecured Senior Notes Due March 30, 2023 [Member] |  |
Debt Instrument [Line Items] |  |
Unsecured senior notes | $ 0 | 249,940
Debt instrument, interest rate | 3.625% |
Debt Instrument, Unamortized Discount |  | 50
Unsecured Senior Notes [Member] | 3.50% Unsecured Senior Notes Due November 1, 2027 [Member] |  |
Debt Instrument [Line Items] |  |
Unsecured senior notes | $ 298,869 | 298,502
Debt instrument, interest rate | 3.50% |
Debt Instrument, Unamortized Discount | $ 876 | 1,161
Unsecured Senior Notes [Member] | 3.35% Unsecured Senior Notes Due September 17, 2029 [Member] |  |
Debt Instrument [Line Items] |  |
Unsecured senior notes | $ 298,294 | 297,997
Debt instrument, interest rate | 3.35% |
Debt Instrument, Unamortized Discount | $ 1,421 | 1,668
Unsecured Senior Notes [Member] | 7.35% Unsecured Senior Notes Due August 15, 2034 [Member] |  |
Debt Instrument [Line Items] |  |
Unsecured senior notes | $ 129,076 | 129,004
Debt instrument, interest rate | 7.35% |
Debt Instrument, Unamortized Discount | $ 731 | 800
Unsecured Senior Notes [Member] | 5.0% Unsecured Senior Notes Due March 30, 2043 [Member] |  |
Debt Instrument [Line Items] |  |
Unsecured senior notes | $ 245,451 | 245,214
Debt instrument, interest rate | 5.00% |
Debt Instrument, Unamortized Discount | $ 4,311 | 4,535
Unsecured Senior Notes [Member] | 5.0% Unsecured Senior Notes Due April 5, 2046 [Member] |  |
Debt Instrument [Line Items] |  |
Unsecured senior notes | $ 493,860 | 493,585
Debt instrument, interest rate | 5.00% |
Debt Instrument, Unamortized Discount | $ 5,445 | 5,689
Unsecured Senior Notes [Member] | 4.30% Unsecured Senior Notes Due November 1, 2047 [Member] |  |
Debt Instrument [Line Items] |  |
Unsecured senior notes | $ 295,870 | 295,691
Debt instrument, interest rate | 4.30% |
Debt Instrument, Unamortized Discount | $ 3,516 | 3,669
Unsecured Senior Notes [Member] | 5.0% Unsecured Senior Notes Due May 20, 2049 [Member] [Domain] |  |
Debt Instrument [Line Items] |  |
Unsecured senior notes | $ 592,233 | 591,927
Debt instrument, interest rate | 5.00% |
Debt Instrument, Unamortized Discount | $ 6,639 | 6,900
Unsecured Senior Notes [Member] | 4.15% Unsecured Senior Notes Due September 17 2050 [Member] |  |
Debt Instrument [Line Items] |  |
Unsecured senior notes | $ 494,546 | 494,342
Debt instrument, interest rate | 4.15% |
Debt Instrument, Unamortized Discount | $ 4,740 | 4,917
Unsecured Senior Notes [Member] | 3.45% Unsecured Senior Notes due May 7 2052 |  |
Debt Instrument [Line Items] |  |
Unsecured senior notes | $ 591,000 | 590,689
Debt instrument, interest rate | 3.45% |
Debt Instrument, Unamortized Discount | $ 7,904 |
Other Debt [Member] |  |
Debt Instrument [Line Items] |  |
Senior long-term debt and other debt | $ 340,597 | $ 416,738
Other Debt [Member] | Other Debt [Member] | Weighted Average |  |
Debt Instrument [Line Items] |  |
Debt instrument, interest rate | 5.00% | 3.40%

X
- Definition Amount of short-term and long-term debt and lease obligation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.13,16) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1 + Details
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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1B -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1 + 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 Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -SubTopic 10 -Topic 210 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)(a)(2)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1 + Details
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