Condensed Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 25, 2021	Sep. 26, 2020	Sep. 25, 2021	Sep. 26, 2020
Net income (loss)	$ 23,733	$ (6,646)	$ 146,436	$ (28,662)
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	(5,206)	11,692	(12,562)	12,660
Adjustments related to postretirement benefits	44	0	15	0
Change in unrealized gain/loss on investments	(11)	0	(25)	0
Reclassifications due to sale of PCB Test business	0	0	(2,515)	0
Other comprehensive income (loss), net of tax	(5,173)	11,692	(15,087)	12,660
Comprehensive income (loss)	$ 18,560	$ 5,046	$ 131,349	$ (16,002)