Long-Term Debt, Carrying Value and Fair Value of Debt Outstanding (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2024	Dec. 31, 2023
Carrying Value and Fair Value of Debt Outstanding [Abstract]
Carrying value	$ 1,052,970	$ 1,022,068
Fair value	995,450	948,641
Unamortized debt discounts and issuance costs	(4,880)	(5,473)
Long-term debt	1,048,090	1,016,595
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	$ 483,222	475,920
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	$ 51,681	49,955
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	$ 207,577	200,698
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	$ 8,970	8,068
Fair value	8,970	8,068
Revolving Credit Facility [Member]
Carrying Value and Fair Value of Debt Outstanding [Abstract]
Carrying value	74,000	44,000
Fair value	$ 74,000	44,000
Maturity Date	Jul. 29, 2027
Term Loan Due July 29, 2027 [Member]
Carrying Value and Fair Value of Debt Outstanding [Abstract]
Carrying value	$ 170,000	170,000
Fair value	$ 170,000	$ 170,000
Variable interest rates	6.60%	6.80%
Maturity Date	Jul. 29, 2027

Debt Instrument Carrying Value And Fair Value Abstract

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- Definition

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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- Definition

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

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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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- Definition

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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