Long-Term Debt, Carrying Value and Fair Value of Debt Outstanding (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2026	Dec. 31, 2025
Carrying Value and Fair Value of Debt Outstanding [Abstract]
Carrying value	$ 1,040,950	$ 922,357
Fair value	1,015,603	904,667
Unamortized debt discounts and issuance costs	(3,602)	(3,076)
Long-term debt	1,037,348	919,281
4.2% Senior Notes Due March 1, 2028 [Member]
Carrying Value and Fair Value of Debt Outstanding [Abstract]
Carrying value	500,000	500,000
Fair value	$ 502,011	$ 506,089
Interest rate	4.20%	4.20%
Maturity Date	Mar. 01, 2028	Mar. 01, 2028
3.46% Senior Notes Due January 19, 2033 [Member]
Carrying Value and Fair Value of Debt Outstanding [Abstract]
Carrying value	$ 60,000	$ 60,000
Fair value	$ 54,387	$ 55,093
Interest rate	3.46%	3.46%
Maturity Date	Jan. 19, 2033	Jan. 19, 2033
3.51% senior notes due January 19, 2033 [Member]
Carrying Value and Fair Value of Debt Outstanding [Abstract]
Carrying value	$ 240,000	$ 240,000
Fair value	$ 218,255	$ 221,128
Interest rate	3.51%	3.51%
Maturity Date	Jan. 19, 2033	Jan. 19, 2033
Credit Line Due June 30, 2028 [Member]
Carrying Value and Fair Value of Debt Outstanding [Abstract]
Carrying value	$ 0	$ 0
Fair value	$ 0	$ 0
Maturity Date	Jun. 30, 2028	Jun. 30, 2028
Bank Note Payable [Member]
Carrying Value and Fair Value of Debt Outstanding [Abstract]
Carrying value	$ 5,950	$ 7,357
Fair value	5,950	7,357
Revolving Credit Facility [Member]
Carrying Value and Fair Value of Debt Outstanding [Abstract]
Carrying value	235,000	45,000
Fair value	$ 235,000	$ 45,000
Variable interest rates	4.60%	5.00%
Maturity Date	Mar. 26, 2031	Mar. 26, 2031
Term Loan Due July 29, 2027 [Member]
Carrying Value and Fair Value of Debt Outstanding [Abstract]
Carrying value	$ 0	$ 70,000
Fair value	$ 0	$ 70,000
Variable interest rates		5.00%
Maturity Date	Jul. 29, 2027	Jul. 29, 2027

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

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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.

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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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- Definition

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

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Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

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Amount, after accumulated amortization, of debt discount.

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Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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