Customer Lists and Other Identifiable Intangible Assets, Net - Reconciliation of Activity for Other Identifiable Intangible Assets (Detail) - Customer Lists and Other Identifiable Intangible Assets [Member] - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Oct. 01, 2017
Finite Lived Intangible Assets [Line Items]
Total Other Identifiable Intangible Assets, Beginning Balance	$ 18,320	$ 10,427
System Transformation Transactions acquisitions		3,800
Additional accumulated amortization	(1,379)	(965)
Total Other Identifiable Intangible Assets, Ending Balance	$ 16,941	$ 13,262