Debt - Debt (Detail) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2026	Dec. 31, 2025
Debt Instrument [Line Items]
Total debt	$ 647,354	$ 626,710
Less current maturities	403,285	285,735
Long-term debt	244,069	340,975
Unsecured private placement 3.95% note [Member]
Debt Instrument [Line Items]
Total debt	$ 28,538	$ 28,515
Debt instrument interest rate percentage	3.95%	3.95%
Unsecured private placement 3.95% note [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Maturity Dates	2026	2026
Unsecured private placement 3.95% note [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Maturity Dates	2027	2027
Unsecured private placement 2.30% note [Member]
Debt Instrument [Line Items]
Total debt	$ 19,956	$ 29,945
Debt instrument interest rate percentage	2.30%	2.30%
Unsecured private placement 2.30% note [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Maturity Dates	2026	2026
Unsecured private placement 2.30% note [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Maturity Dates	2028	2028
Unsecured private placement 2.37% note [Member]
Debt Instrument [Line Items]
Total debt	$ 29,951	$ 29,940
Debt instrument interest rate percentage	2.37%	2.37%
Unsecured private placement 2.37% note [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Maturity Dates	2026	2026
Unsecured private placement 2.37% note [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Maturity Dates	2028	2028
Unsecured private placement 2.73% note [Member]
Debt Instrument [Line Items]
Total debt	$ 85,670	$ 85,662
Debt instrument interest rate percentage	2.73%	2.73%
Unsecured private placement 2.73% note [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Maturity Dates	2026	2026
Unsecured private placement 2.73% note [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Maturity Dates	2031	2031
Unsecured private placement 2.83% note [Member]
Debt Instrument [Line Items]
Total debt	$ 64,239	$ 74,948
Debt instrument interest rate percentage	2.83%	2.83%
Unsecured private placement 2.83% note [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Maturity Dates	2026	2026
Unsecured private placement 2.83% note [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Maturity Dates	2032	2032
Unsecured private placement 6.17% note [Member]
Debt Instrument [Line Items]
Total debt	$ 75,000	$ 75,000
Debt instrument interest rate percentage	6.17%	6.17%
Unsecured private placement 6.17% note [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Maturity Dates	2029	2029
Unsecured private placement 6.17% note [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Maturity Dates	2033	2033
Revolving credit facility and term loan borrowing [Member]
Debt Instrument [Line Items]
Total debt	$ 344,000	$ 302,700
Revolving credit facility and term loan borrowing [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Maturity Dates	2026	2026
Revolving credit facility and term loan borrowing [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Maturity Dates	2027	2027

Debt instruments maturity year.

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- Definition

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

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