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Divestitures - SAFE&CEC S.r.l. (Details) - USD ($) $ in Thousands		12 Months Ended
	Dec. 29, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Jan. 02, 2019
Acquisitions and Divestitures
Gain from sale of certain assets of subsidiary		$ 7,455	$ 4,782	$ 70,658
Working capital adjustments, funding for certain post-closing commitments, and transaction fees		13,142	14,381
Loss before income taxes		(14,117)	8,842	83,305
Accrued liabilities		67,697	48,469		$ 47,973
Income (loss) from equity method investments		(119)	(2,723)	(131)
CEC
Acquisitions and Divestitures
Loss before income taxes				45,100
SAFE&CEC S.r.l.
Acquisitions and Divestitures
Ownership interest (as a percent)	49.00%
Gain from sale of certain assets of subsidiary				$ 6,500
Working capital adjustments, funding for certain post-closing commitments, and transaction fees		1,000	3,300
Goodwill reduced during the year	$ 3,600
Accrued liabilities		1,200
Income (loss) from equity method investments		0	(2,900)
Investment balance		$ 23,700	$ 23,400
SAFE&CEC S.r.l. \| Landi Renzo S.p.A.
Acquisitions and Divestitures
Ownership interest (as a percent)	51.00%