v3.26.1
Postretirement Benefit Plans - Components of Net Periodic Benefit Cost (Detail) - USD ($)
$ in Thousands
3 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Defined Benefit Plan Disclosure [Line Items]    
Net periodic benefit cost $ (31) $ (255)
United States [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Interest cost 1,646 1,700
Expected return on plan assets (1,848) (2,002)
Amortization of net actuarial loss (gain) 108 (19)
Net periodic benefit cost (94) (321)
United Kingdom [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Interest cost 179 168
Expected return on plan assets (202) (194)
Amortization of net actuarial loss (gain) 85 92
Net periodic benefit cost $ 62 $ 66