Long-Term Debt, Carrying Value and Fair Value of Debt Outstanding (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2025	Dec. 31, 2024
Carrying Value and Fair Value of Debt Outstanding [Abstract]
Carrying value	$ 1,121,433	$ 878,226
Fair value	1,097,060	835,755
Unamortized debt discounts and issuance costs	(3,668)	(3,278)
Long-term debt	1,117,765	874,948
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	$ 502,539	491,923
Interest rate	4.20%
Maturity Date	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	$ 54,459	52,956
Interest rate	3.46%
Maturity Date	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	$ 218,629	212,650
Interest rate	3.51%
Maturity Date	Jan. 19, 2033
Credit Line Due June 30, 2026 [Member]
Carrying Value and Fair Value of Debt Outstanding [Abstract]
Carrying value	$ 0	0
Fair value	$ 0	0
Maturity Date	Jun. 30, 2026
Bank Note Payable [Member]
Carrying Value and Fair Value of Debt Outstanding [Abstract]
Carrying value	$ 6,433	8,226
Fair value	6,433	8,226
Revolving Credit Facility [Member]
Carrying Value and Fair Value of Debt Outstanding [Abstract]
Carrying value	245,000	0
Fair value	$ 245,000	0
Maturity Date	Jul. 29, 2027
Term Loan Due July 29, 2027 [Member]
Carrying Value and Fair Value of Debt Outstanding [Abstract]
Carrying value	$ 70,000	70,000
Fair value	$ 70,000	$ 70,000
Variable interest rates	5.60%	5.60%
Maturity Date	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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- Definition

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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