Condensed Consolidated Statements of Comprehensive Income (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Sep. 28, 2014	Sep. 29, 2013	Sep. 28, 2014	Sep. 29, 2013
Statement of Comprehensive Income [Abstract]
Net income	$ 11,010	$ 10,977	$ 17,010	$ 7,927
Changes in fair value of marketable securities:
Changes in unrealized gains	(347)	602	(148)	(1,319)
Net realized losses (gains) reclassified into earnings	64	135	127	(259)
Total changes in fair value of marketable securities	(283)	737	(21)	(1,578)
Foreign currency translation adjustments	(269)	252	(211)	(42)
Total other comprehensive income (loss)	(552)	989	(232)	(1,620)
Comprehensive income	$ 10,458	$ 11,966	$ 16,778	$ 6,307

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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