Accumulated Other Comprehensive Income (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 02, 2021	Jun. 26, 2020	Jul. 02, 2021	Jun. 26, 2020	Apr. 02, 2021	Dec. 31, 2020	Mar. 27, 2020	Dec. 31, 2019
Accumulated Other Comprehensive Income (Loss) [Rollforward]
Accumulated other comprehensive loss	$ (43,084)	$ (45,571)	$ (43,084)	$ (45,571)	$ (46,087)	$ (38,639)	$ (47,173)	$ (45,462)
Activity
Other comprehensive income (loss) before reclassifications	4,282	980	(1,458)	(1,636)
Amounts reclassified from accumulated other comprehensive income (loss)	(1,365)	701	(2,706)	1,315
Net current period other comprehensive income (loss) before tax	2,917	1,681	(4,164)	(321)
Deferred taxes	(86)	79	281	(212)
Other comprehensive income (loss)	3,003	1,602	(4,445)	(109)
Pension and Post Employment Benefits [Member]
Accumulated Other Comprehensive Income (Loss) [Rollforward]
Accumulated other comprehensive loss	(43,226)	(41,241)	(43,226)	(41,241)	(43,309)	(43,473)	(41,330)	(41,346)
Activity
Other comprehensive income (loss) before reclassifications	0	0	0	0
Amounts reclassified from accumulated other comprehensive income (loss)	77	70	234	46
Net current period other comprehensive income (loss) before tax	77	70	234	46
Deferred taxes	(6)	(19)	(13)	(59)
Other comprehensive income (loss)	83	89	247	105
Foreign Currency Translation [Member]
Accumulated Other Comprehensive Income (Loss) [Rollforward]
Accumulated other comprehensive loss	(1,647)	(4,720)	(1,647)	(4,720)	(4,840)	4,017	(5,886)	(5,013)
Activity
Other comprehensive income (loss) before reclassifications	3,193	1,166	(5,664)	293
Amounts reclassified from accumulated other comprehensive income (loss)	0	0	0	0
Net current period other comprehensive income (loss) before tax	3,193	1,166	(5,664)	293
Deferred taxes	0	0	0	0
Other comprehensive income (loss)	3,193	1,166	(5,664)	293
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Rollforward]
Accumulated other comprehensive loss	1,789	390	1,789	390	2,062	817	43	897
Activity
Other comprehensive income (loss) before reclassifications	1,089	(186)	4,206	(1,929)
Amounts reclassified from accumulated other comprehensive income (loss)	(1,442)	631	(2,940)	1,269
Net current period other comprehensive income (loss) before tax	(353)	445	1,266	(660)
Deferred taxes	(80)	98	294	(153)
Other comprehensive income (loss)	(273)	347	972	(507)
Foreign currency forward contract | Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Rollforward]
Accumulated other comprehensive loss	1,603	1,065	1,603	1,065	1,462	519	1,214	1,324
Activity
Other comprehensive income (loss) before reclassifications	183	(201)	1,268	(343)
Amounts reclassified from accumulated other comprehensive income (loss)	0	8	140	7
Net current period other comprehensive income (loss) before tax	183	(193)	1,408	(336)
Deferred taxes	42	(44)	324	(77)
Other comprehensive income (loss)	141	(149)	1,084	(259)
Precious Metal Contracts [Member] | Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Rollforward]
Accumulated other comprehensive loss	186	(779)	186	(779)	320	(170)	(841)	(452)
Activity
Other comprehensive income (loss) before reclassifications	(239)	(411)	502	(1,234)
Amounts reclassified from accumulated other comprehensive income (loss)	65	491	(39)	809
Net current period other comprehensive income (loss) before tax	(174)	80	463	(425)
Deferred taxes	(40)	18	107	(98)
Other comprehensive income (loss)	(134)	62	356	(327)
Copper swaps | Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Rollforward]
Accumulated other comprehensive loss	0	104	0	104	$ 280	$ 468	$ (330)	$ 25
Activity
Other comprehensive income (loss) before reclassifications	1,145	426	2,436	(352)
Amounts reclassified from accumulated other comprehensive income (loss)	(1,507)	132	(3,041)	453
Net current period other comprehensive income (loss) before tax	(362)	558	(605)	101
Deferred taxes	(82)	124	(137)	22
Other comprehensive income (loss)	$ (280)	$ 434	$ (468)	$ 79