Post-Retirement Health Care (Schedule of Cost of Retirement Plans) (Details) - Other postretirement plans - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Jan. 02, 2016
Change in benefit obligation
Benefit obligation at beginning of year	$ 20,884	$ 21,972
Service cost	735	803
Interest cost	846	816
Benefits paid	(1,017)	(1,009)
Actuarial (gain)/loss	(295)	(1,698)
Benefit obligation at end of year	21,153	20,884
Change in plan assets
Fair value at beginning of year	0	0
Actual return on assets	0	0
Employer contribution	1,017	1,009
Transferred out	0	0
Fair value at end of year	0	0
Funded Status of Plan	(21,153)	(20,884)
Amounts recognized in the Statement of Financial Position consist of:
Current liabilities	1,034	1,014
Noncurrent liabilities	20,119	19,870
Amounts recognized in Accumulated Other Comprehensive Income (before tax) consist of:
Actuarial (gain)/loss	2,373	2,730
Change in Accumulated Other Comprehensive Income (before tax):
Amount disclosed at beginning of year	2,730	4,665
Actuarial (gain)/loss	(295)	(1,698)
Amortization of transition amount	(62)	(237)
Amount disclosed at end of year	$ 2,373	$ 2,730

Change in Accumulated Other Comprehensive Income, Before tax [Roll Forward]

No definition available.

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The pretax total of net gain (loss), prior service cost (credit), and transition assets (obligations), as well as minimum pension liability if still remaining, included in accumulated other comprehensive income associated with a defined benefit pension or other postretirement plan(s) because they have yet to be recognized as components of net periodic benefit cost.