Income taxes - Components of Comprehensive Provision (Benefit) for Income Taxes Allocation (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Comprehensive provision (benefit) for income taxes allocable to:
Net income	$ (23)	$ 988
Other comprehensive income (loss):
Currency translation	1,112	(1,320)
Other	(9)	(8)
Total	1,165	(239)
Defined Benefit Pension Plans
Other comprehensive income (loss):
Pension plans	$ 85	$ 101