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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%

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