Stockholders' equity - Schedule of Changes in Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period			$ 382,150
Plan settlement	$ 0	$ 0	4,142	$ 0
Balance at end of period	364,239		364,239
Currency Translation
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	(181,076)	(178,396)	(178,191)	(171,235)
Other comprehensive loss	(345)	(6,233)	(3,230)	(13,394)
Balance at end of period	(181,421)	(184,629)	(181,421)	(184,629)
Accumulated Defined Benefit Plans Adjustment | Defined Benefit Pension Plans
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	(38,788)	(66,739)	(43,857)	(68,468)
Other comprehensive loss	392	828	1,319	2,557
Balance at end of period	(38,396)	(65,911)	(38,396)	(65,911)
Accumulated Defined Benefit Plans Adjustment | OPEB
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	(1,011)	(1,184)	(893)	(1,053)
Other comprehensive loss	(57)	(62)	(175)	(193)
Balance at end of period	(1,068)	(1,246)	(1,068)	(1,246)
Marketable Securities
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	(223)	0	(50)	0
Other comprehensive loss	81	0	(92)	0
Balance at end of period	(142)	0	(142)	0
Accumulated other comprehensive loss
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	(221,098)	(246,319)	(222,991)	(240,756)
Other comprehensive loss	71	(5,467)	1,964	(11,030)
Balance at end of period	$ (221,027)	$ (251,786)	$ (221,027)	$ (251,786)