Details of Finite-lived Intangible Assets by Segment (Detail) - USD ($) $ in Thousands	Jul. 01, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Finite Lived, Gross Carrying Amount	$ 8,387
Accumulated Amortization	(6,556)	$ (6,129)
Finite Lived, Net Carrying Amount	1,831	$ 2,258
Thin-film Equipment Segment
Finite-Lived Intangible Assets [Line Items]
Finite Lived, Gross Carrying Amount	7,172
Accumulated Amortization	(5,505)
Finite Lived, Net Carrying Amount	1,667
Photonics
Finite-Lived Intangible Assets [Line Items]
Finite Lived, Gross Carrying Amount	1,215
Accumulated Amortization	(1,051)
Finite Lived, Net Carrying Amount	$ 164