Fair Value Measurements - Investments (Details) - USD ($) $ in Thousands	12 Months Ended
Apr. 01, 2017	Apr. 02, 2016
Available for sale Securities Current
Schedule of Available-for-sale Securities
Available-for-sale Securities	$ 10,688	$ 26,389
Unrealized Gain	0	5
Unrealized Loss	0	0
Cost	10,688	26,384
Available for sale Securities Current \| Commercial Paper
Schedule of Available-for-sale Securities
Available-for-sale Securities	10,688	13,137
Unrealized Gain	0	0
Unrealized Loss	0	0
Cost	10,688	13,137
Available for sale Securities Current \| Government agencies
Schedule of Available-for-sale Securities
Available-for-sale Securities		13,252
Unrealized Gain		5
Unrealized Loss		0
Cost		13,247
Available for sale Securities Non Current
Schedule of Available-for-sale Securities
Available-for-sale Securities	3,058	2,504
Unrealized Gain	84	0
Unrealized Loss	0	(3)
Cost	2,974	2,507
Available for sale Securities Non Current \| Exchange Traded Funds [Member]
Schedule of Available-for-sale Securities
Available-for-sale Securities	3,058
Unrealized Gain	84
Unrealized Loss	0
Cost	$ 2,974
Available for sale Securities Non Current \| Municipal Bonds
Schedule of Available-for-sale Securities
Available-for-sale Securities		2,504
Unrealized Gain		0
Unrealized Loss		(3)
Cost		$ 2,507

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=65884222&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27232-111563

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66010992&loc=d3e26610-111562

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.2)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Amount of unrealized gain before deducting unrealized loss on investments in debt and equity securities classified as available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563

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Amount of unrealized loss before deducting unrealized gain on investments in available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27161-111563

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