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Derivative Instruments and Hedging Activities (Effects of the interest rate swaps) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jul. 01, 2018	Jun. 30, 2019	Jul. 01, 2018	Dec. 30, 2018
Derivative [Line Items]
Total effects of the interest rate swaps on Net income	$ (130)	$ (71)	$ 234	$ (379)
Interest rate swap [Member] \| Designated as hedging instrument [Member]
Derivative [Line Items]
Total effects of the interest rate swaps on Net income	(130)	(71)	234	(379)
Derivative, net liability position, aggregate fair value	26,600		26,600		$ 10,500
Derivative, termination value	26,600		26,600		$ 10,500
Interest rate swap [Member] \| Designated as hedging instrument [Member] \| Interest expense [Member]
Derivative [Line Items]
Interest rate swap (expense) benefit recognized in Interest expense, net	(175)	(95)	316	(510)
Interest rate swap [Member] \| Designated as hedging instrument [Member] \| Income tax expense [Member]
Derivative [Line Items]
Income tax benefit (expense) recognized in Provision (benefit) for income taxes	$ 45	$ 24	$ (82)	$ 131