Stockholders' equity - Schedule of Changes in Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period			$ 369,812
Balance at end of period	$ 386,037		386,037
Currency Translation
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	(181,619)	$ (181,076)	(177,119)	$ (178,191)
Other comprehensive income (loss)	1,521	(345)	(2,979)	(3,230)
Balance at end of period	(180,098)	(181,421)	(180,098)	(181,421)
Accumulated Defined Benefit Plans Adjustment | Defined Benefit Pension Plans
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	(40,616)	(38,788)	(41,373)	(43,857)
Other comprehensive income (loss)	378	392	1,135	1,319
Plan settlement				4,142
Balance at end of period	(40,238)	(38,396)	(40,238)	(38,396)
Other | OPEB plans
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	(1,206)	(1,011)	(1,114)	(893)
Other comprehensive income (loss)	(45)	(57)	(137)	(175)
Balance at end of period	(1,251)	(1,068)	(1,251)	(1,068)
Marketable debt securities
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	7	(223)	(15)	(50)
Other comprehensive income (loss)	(7)	81	15	(92)
Balance at end of period	0	(142)	0	(142)
Total accumulated other comprehensive loss
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	(223,434)	(221,098)	(219,621)	(222,991)
Other comprehensive income (loss)	1,847	71	(1,966)	1,964
Balance at end of period	$ (221,587)	$ (221,027)	$ (221,587)	$ (221,027)