Accumulated Other Comprehensive Income (Schedule of Accumulated Other Comprehensive Income) (Details) - Accumulated Net Investment Gain (Loss) Attributable to Parent [Member] $ in Thousands	3 Months Ended
	Apr. 01, 2017 USD ($)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive income balance, beginning balance	$ 4,852
Other comprehensive income before reclassifications	64
Amounts reclassified from accumulated other comprehensive income	0
Net current period other comprehensive income	64
Accumulated other comprehensive income balance, ending balance	$ 4,916