Goodwill and Identified Intangible Assets - Summary of Goodwill and Identified Intangible Assets (Detail) - USD ($) $ in Thousands	6 Months Ended
	Jun. 29, 2018	Dec. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 85,655	$ 85,857
Accumulated Amortization	(68,645)	(64,578)
Total future amortization expense	$ 17,010	21,279
Developed Core Technology
Finite-Lived Intangible Assets [Line Items]
Useful Life	1 year 8 months 12 days
Gross Carrying Amount	$ 31,707	31,707
Accumulated Amortization	(22,985)	(20,396)
Total future amortization expense	$ 8,722	11,311
Customer relationships/contracts
Finite-Lived Intangible Assets [Line Items]
Useful Life	2 years 8 months 12 days
Gross Carrying Amount	$ 44,690	44,819
Accumulated Amortization	(36,664)	(35,205)
Total future amortization expense	$ 8,026	9,614
Trademarks and Trade Names
Finite-Lived Intangible Assets [Line Items]
Useful Life	1 year 8 months 12 days
Gross Carrying Amount	$ 630	654
Accumulated Amortization	(368)	(300)
Total future amortization expense	262	354
Maintenance Agreements and Related Relationships
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	5,500	5,500
Accumulated Amortization	(5,500)	(5,500)
Total future amortization expense	0	0
Order Backlog
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	3,128	3,177
Accumulated Amortization	(3,128)	(3,177)
Total future amortization expense	$ 0	$ 0