Employee Benefit Plans (Schedule of Effect of Significant Unobservable Inputs, Changes in Plan Assets, Other Postretirement Benefit Plans) (Details) - Other Postretirement Benefits Plan [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Jan. 01, 2017	Jan. 03, 2016
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at beginning of year	$ 15,453	$ 14,353
Realized gains (losses)	741	539	$ (971)
Fair value of plan assets at end of year	17,374	15,453	14,353
Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at beginning of year	1,508
Fair value of plan assets at end of year	1,151	1,508
Multi-strategy hedge funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at beginning of year	1,508
Fair value of plan assets at end of year	1,151	1,508
Multi-strategy hedge funds [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets Level 3 Reconciliation, Increase (Decrease) for Purchases, Sales, and Settlements	(562)
Fair value of plan assets at beginning of year	1,508	1,374	1,341
Realized gains (losses)	229
Unrealized gains (losses)	(24)	134	33
Fair value of plan assets at end of year	$ 1,151	$ 1,508	$ 1,374