Goodwill and Purchased Intangible Assets - Purchased Intangible Assets (Detail) - USD ($) $ in Thousands			6 Months Ended
	Apr. 15, 2019	Aug. 27, 2018	Jun. 28, 2019	Dec. 28, 2018
Finite-Lived Intangible Assets [Line Items]
Definite lives intangible assets, accumulated amortization			$ (51,557)	$ (41,650)
Definite lives intangible assets, net carrying amount			181,513
Intangible Assets, gross carrying value			242,057	235,157
Intangible Assets, net carrying value			190,500	193,507
American Integration Technologies LLC [Member] | Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Definite lives intangible assets, gross carrying amount			19,000	19,000
Definite lives intangible assets, accumulated amortization			(18,808)	(18,617)
Definite lives intangible assets, net carrying amount			$ 192	383
Useful Life (in years)			7 years
American Integration Technologies LLC [Member] | Trade Name [Member]
Finite-Lived Intangible Assets [Line Items]
Definite lives intangible assets, gross carrying amount			$ 1,900	1,900
Definite lives intangible assets, accumulated amortization			$ (1,900)	(1,900)
Useful Life (in years)			6 years
American Integration Technologies LLC [Member] | Intellectual Properties/Know-How [Member]
Finite-Lived Intangible Assets [Line Items]
Definite lives intangible assets, gross carrying amount			$ 1,600	1,600
Definite lives intangible assets, accumulated amortization			$ (1,600)	(1,486)
Definite lives intangible assets, net carrying amount				114
Useful Life (in years)			7 years
Thermal [Member] | Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Definite lives intangible assets, gross carrying amount			$ 9,900	9,900
Definite lives intangible assets, accumulated amortization			(4,373)	(3,877)
Definite lives intangible assets, net carrying amount			$ 5,527	6,023
Useful Life (in years)			10 years
Thermal [Member] | Trade Name [Member]
Finite-Lived Intangible Assets [Line Items]
Definite lives intangible assets, gross carrying amount			$ 1,170	1,170
Definite lives intangible assets, accumulated amortization			$ (1,170)	(1,170)
Useful Life (in years)			6 years
Thermal [Member] | Intellectual Properties/Know-How [Member]
Finite-Lived Intangible Assets [Line Items]
Definite lives intangible assets, gross carrying amount			$ 12,300	12,300
Definite lives intangible assets, accumulated amortization			(6,091)	(5,402)
Definite lives intangible assets, net carrying amount			$ 6,209	6,898
Thermal [Member] | Intellectual Properties/Know-How [Member] | Minimum [Member]
Finite-Lived Intangible Assets [Line Items]
Useful Life (in years)			8 years
Thermal [Member] | Intellectual Properties/Know-How [Member] | Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Useful Life (in years)			12 years
FDS [Member] | Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Definite lives intangible assets, gross carrying amount			$ 8,800	8,800
Definite lives intangible assets, accumulated amortization			(4,596)	(4,009)
Definite lives intangible assets, net carrying amount			$ 4,204	4,791
Useful Life (in years)			7 years 6 months
Quantum Global Technologies, LLC [Member] | Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Definite lives intangible assets, gross carrying amount			$ 74,800	74,800
Definite lives intangible assets, accumulated amortization			(6,233)	(2,500)
Definite lives intangible assets, net carrying amount			$ 68,567	72,300
Useful Life (in years)		10 years	10 years
Quantum Global Technologies, LLC [Member] | Trade Name [Member]
Finite-Lived Intangible Assets [Line Items]
Definite lives intangible assets, gross carrying amount			$ 14,900	14,900
Definite lives intangible assets, accumulated amortization			(3,186)	(1,326)
Definite lives intangible assets, net carrying amount			$ 11,714	13,574
Useful Life (in years)		4 years	4 years
Quantum Global Technologies, LLC [Member] | Recipes [Member]
Finite-Lived Intangible Assets [Line Items]
Definite lives intangible assets, gross carrying amount			$ 73,200	73,200
Definite lives intangible assets, accumulated amortization			(3,050)	(1,220)
Definite lives intangible assets, net carrying amount			$ 70,150	71,980
Useful Life (in years)		20 years	20 years
Quantum Global Technologies, LLC [Member] | Standard Operating Procedures [Member]
Finite-Lived Intangible Assets [Line Items]
Definite lives intangible assets, gross carrying amount			$ 8,600	8,600
Definite lives intangible assets, accumulated amortization			(358)	(143)
Definite lives intangible assets, net carrying amount			$ 8,242	8,457
Useful Life (in years)		20 years	20 years
Dynamic Manufacturing Solutions [Member] | Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Definite lives intangible assets, gross carrying amount			$ 6,900
Definite lives intangible assets, accumulated amortization			(192)
Definite lives intangible assets, net carrying amount			$ 6,708
Useful Life (in years)	6 years		6 years
UCT [Member] | Trade Name [Member]
Finite-Lived Intangible Assets [Line Items]
Indefinite lives intangible assets			$ 8,987	$ 8,987