Debt - Debt (Detail) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2025	Dec. 31, 2024
Debt Instrument [Line Items]
Total debt	$ 655,472	$ 625,439
Less current maturities	298,365	292,807
Long-term debt	357,107	332,632
Unsecured private placement 3.95% note [Member]
Debt Instrument [Line Items]
Total debt	$ 28,505	$ 42,759
Debt instrument interest rate percentage	3.95%	3.95%
Unsecured private placement 3.95% note [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Maturity Dates	2025	2025
Unsecured private placement 3.95% note [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Maturity Dates	2027	2027
Unsecured private placement 3.86% note [Member]
Debt Instrument [Line Items]
Total debt	$ 0	$ 14,270
Debt instrument interest rate percentage	3.86%	3.86%
Unsecured private placement 3.86% note [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Maturity Dates	2025	2025
Unsecured private placement 2.30% note [Member]
Debt Instrument [Line Items]
Total debt	$ 29,940	$ 39,923
Debt instrument interest rate percentage	2.30%	2.30%
Unsecured private placement 2.30% note [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Maturity Dates	2025	2025
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	$ 29,934	$ 39,917
Debt instrument interest rate percentage	2.37%	2.37%
Unsecured private placement 2.37% note [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Maturity Dates	2025	2025
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	$ 99,943	$ 99,930
Debt instrument interest rate percentage	2.73%	2.73%
Unsecured private placement 2.73% note [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Maturity Dates	2025	2025
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	$ 74,946	$ 74,940
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	$ 0
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
Debt of foreign subsidiaries Unsecured bank debt, foreign currency [Member]
Debt Instrument [Line Items]
Total debt	$ 2,504	$ 0
Maturity Dates	2025	2025
Revolving credit facility and term loan borrowing [Member]
Debt Instrument [Line Items]
Total debt	$ 314,700	$ 313,700
Revolving credit facility and term loan borrowing [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Maturity Dates	2025	2025
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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