Income Taxes - Components of Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Deferred tax assets:
Pension liability	$ 16,616	$ 17,359
Accrued warranty expense	1,829	1,570
Capitalized Section 174 expenditures	57,870	64,775
Accrued vacation pay	2,721	2,434
Accrued liabilities for executive and employee incentive compensation	22,834	18,736
Environmental and products liabilities	21,220	20,945
Lease liabilities	5,136	5,055
Investments in joint ventures and affiliated companies	3,065	2,746
Convertible debt premium	34,275	0
U.S. federal tax credits and loss carryforward	3,399	3,071
U.S. state tax credits and loss carryforward	11,545	10,119
Foreign tax credit and loss carryforward	19,820	23,394
Other	1,145	1,692
Gross deferred tax assets	201,475	171,896
Valuation allowance for deferred tax assets	(14,939)	(17,039)
Total deferred tax assets	186,536	154,857
Deferred tax liabilities:
Property, plant and equipment	105,046	88,090
Long-term contracts	24,937	54,714
Right-of-use lease assets	10,947	10,590
Accrued liabilities for self-insurance (including postretirement health care benefits)	58,033	19,589
Intangibles	502	826
Total deferred tax liabilities	199,465	173,809
Net deferred tax liabilities	$ (12,929)	$ (18,952)

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