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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, 2024	May 15, 2024	Dec. 31, 2023
Debt Instrument [Line Items]
Senior long-term debt and other debt	$ 4,330,341		$ 3,779,796
Unsecured Senior Notes [Member]
Debt Instrument [Line Items]
Senior long-term debt and other debt	4,032,959
Unsecured Senior Notes [Member] | 3.50% Unsecured Senior Notes Due November 1, 2027 [Member]
Debt Instrument [Line Items]
Unsecured senior notes	$ 299,236		298,869
Debt instrument, interest rate	3.50%
Debt Instrument, Unamortized Discount	$ 592		876
Unsecured Senior Notes [Member] | 3.35% Unsecured Senior Notes Due September 17, 2029 [Member]
Debt Instrument [Line Items]
Unsecured senior notes	$ 298,590		298,294
Debt instrument, interest rate	3.35%
Debt Instrument, Unamortized Discount	$ 1,174		1,421
Unsecured Senior Notes [Member] | 7.35% Unsecured Senior Notes Due August 15, 2034 [Member]
Debt Instrument [Line Items]
Unsecured senior notes	$ 129,148		129,076
Debt instrument, interest rate	7.35%
Debt Instrument, Unamortized Discount	$ 663		731
Unsecured Senior Notes [Member] | 5.0% Unsecured Senior Notes Due March 30, 2043 [Member]
Debt Instrument [Line Items]
Unsecured senior notes	$ 245,687		245,451
Debt instrument, interest rate	5.00%
Debt Instrument, Unamortized Discount	$ 4,087		4,311
Unsecured Senior Notes [Member] | 5.0% Unsecured Senior Notes Due April 5, 2046 [Member]
Debt Instrument [Line Items]
Unsecured senior notes	$ 494,135		493,860
Debt instrument, interest rate	5.00%
Debt Instrument, Unamortized Discount	$ 5,202		5,445
Unsecured Senior Notes [Member] | 4.30% Unsecured Senior Notes Due November 1, 2047 [Member]
Debt Instrument [Line Items]
Unsecured senior notes	$ 296,049		295,870
Debt instrument, interest rate	4.30%
Debt Instrument, Unamortized Discount	$ 3,364		3,516
Unsecured Senior Notes [Member] | 5.0% Unsecured Senior Notes Due May 20, 2049 [Member] [Domain]
Debt Instrument [Line Items]
Unsecured senior notes	$ 592,538		592,233
Debt instrument, interest rate	5.00%
Debt Instrument, Unamortized Discount	$ 6,378		6,639
Unsecured Senior Notes [Member] | 4.15% Unsecured Senior Notes Due September 17 2050 [Member]
Debt Instrument [Line Items]
Unsecured senior notes	$ 494,749		494,546
Debt instrument, interest rate	4.15%
Debt Instrument, Unamortized Discount	$ 4,563		4,740
Unsecured Senior Notes [Member] | 3.45% Unsecured Senior Notes due May 7 2052
Debt Instrument [Line Items]
Unsecured senior notes	$ 591,316		591,000
Debt instrument, interest rate	3.45%
Debt Instrument, Unamortized Discount	$ 7,626		7,904
Unsecured Senior Notes [Member] | 6.0% Unsecured Senior Notes due May 16 2054
Debt Instrument [Line Items]
Unsecured senior notes	$ 591,511		0
Debt instrument, interest rate	6.00%	6.00%
Debt Instrument, Unamortized Discount	$ 7,240		0
Other Debt [Member]
Debt Instrument [Line Items]
Senior long-term debt and other debt	$ 297,382		$ 340,597
Other Debt [Member] | Other Debt [Member] | Weighted Average
Debt Instrument [Line Items]
Debt instrument, interest rate	5.40%		5.00%

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