Accumulated Other Comprehensive Income (Tables)

3 Months Ended

Mar. 26, 2016

Accumulated Other Comprehensive Income [Abstract]

Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]

		Unrealized Gains
		on Available-for-Sale
(dollars in thousands)		Marketable Securities
Accumulated other comprehensive income balance as of December 26, 2015	$	4,761
Other comprehensive income before reclassifications		816
Amounts reclassified from accumulated other comprehensive income		(158)
Net current period other comprehensive income		658
Accumulated other comprehensive income balance as of March 26, 2016	$	5,419

Reclassification out of Accumulated Other Comprehensive Income [Table Text Block]

		Gains Reclassified from
		Accumulated Other Comprehensive Income to the
		Consolidated Statements of Income
		13 Weeks Ended
(dollars in thousands)	Location		March 26, 2016		March 28, 2015
Unrealized gains on available-for-sale marketable securities
	Investment income	$	269	$	6
	Provision for income taxes		(111)		(3)
Total amount reclassified, net of tax		$	158	$	3