Consolidated Condensed Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
Jun. 30, 2018	Jun. 24, 2017
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ (4,272)	$ 42,912
Other comprehensive income (loss), before tax
Foreign currency translation gain (loss)	(2,190)	290
Unrealized gain on marketable securities	41	34
Actuarial gain on pension plan	0	792
Provision for income taxes	(8)	(150)
Comprehensive income (loss)	$ (6,429)	$ 43,878

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount before tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount before tax and reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities and unrealized holding gain (loss) related to transfers of securities into the available-for-sale classification and out of the held-to-maturity classification.

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Amount, before tax, of gain (loss) for (increase) decrease in value of benefit obligation for change in actuarial assumptions and increase (decrease) in value of plan assets from experience different from that assumed of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

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