Restructuring Charges (Separation and Restructuring Plan Activity) (Detail) - USD ($) $ in Thousands		6 Months Ended	12 Months Ended
	Jul. 01, 2019	Dec. 31, 2020	Jun. 30, 2020
Restructuring Cost and Reserve [Line Items]
Liability beginning balance	$ 25,083	$ 1,435	$ 25,083
Increase in liability (separation and other charges)		490	4,955
Reduction in liability (payments and adjustments)		(1,708)	(3,573)
Liability ending balance	53	$ 217	$ 1,435
ASC 842
Restructuring Cost and Reserve [Line Items]
Reduction in liability from ASU implementation	$ (25,030)