Note 14 - Accumulated Other Comprehensive Loss - Components of Other Comprehensive Loss (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Foreign currency translation adjustments, before tax	$ (7,522)	$ (8,905)	$ 11,345
Foreign currency translation adjustments, tax
Foreign currency translation adjustments, net of tax	(7,522)	(8,905)	11,345
Adjustments related to postretirement benefits, before tax	(856)	865	(1,369)
Adjustments related to postretirement benefits, tax	228	(60)	121
Adjustments related to postretirement benefits, net of tax	(628)	805	(1,248)
Change in unrealized gain/loss on investments, before tax		7	(2)
Change in unrealized gain/loss on investments, tax
Change in unrealized gain/loss on investments, net of tax		7	(2)
Other comprehensive income (loss), before tax	(8,378)	(8,033)	9,974
Other comprehensive income (loss), tax	228	(60)	121
Other comprehensive income (loss), net of tax	$ (8,150)	$ (8,093)	$ 10,095

Amount, before tax, after reclassification adjustment, of (increase) decrease in accumulated other comprehensive (income) loss for defined benefit plan, attributable to parent entity.

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