Note 11 - Components of Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Foreign currency translation adjustments	$ (11,000)	$ (14,107)	$ 3,270
Foreign currency translation adjustments
Foreign currency translation adjustments	$ (11,000)	$ (14,107)	$ 3,270
Adjustments related to postretirement benefits	(24)	(3,809)	1,889
Adjustments related to postretirement benefits	(34)	551	(285)
Adjustments related to postretirement benefits	$ 58	$ 3,258	(1,604)
Change in unrealized gain/loss on investments			(14)
Change in unrealized gain/loss on investments			8
Change in unrealized gain/loss on investments			(6)
Other comprehensive income (loss)	$ (11,024)	$ (17,916)	5,145
Other comprehensive income (loss)	(34)	551	(277)
Other comprehensive income (loss)	$ (11,058)	$ (17,365)	$ 4,868

Amount before tax, after reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans, attributable to parent entity.

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