Accumulated Other Comprehensive Income (Loss) (Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Apr. 01, 2017
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss) - total	$ (1,299)
Unrealized gain on interest rate swaps, net	804	$ 35
Reclassification of loss into earnings from interest rate swaps, net	228	223
Reclassification of net actuarial gain into earnings from postretirement benefit plans, net	(7)	(5)
Reclassification of prior service credits into earnings from postretirement benefit plans, net	(1)	$ (1)
Accumulated other comprehensive income (loss) - total	(275)
Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss) - total	(1,587)
Unrealized gain on interest rate swaps, net	804
Reclassification of loss into earnings from interest rate swaps, net	228
Accumulated other comprehensive income (loss) - total	(555)
Accumulated Defined Benefit Plans Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income (loss) - total	288
Reclassification of net actuarial gain into earnings from postretirement benefit plans, net	(7)
Reclassification of prior service credits into earnings from postretirement benefit plans, net	(1)
Accumulated other comprehensive income (loss) - total	$ 280