Fair Value Measurements - Investments (Details) - USD ($) $ in Thousands	Oct. 01, 2016	Apr. 02, 2016
Available for sale Securities Current
Schedule of Available-for-sale Securities
Cost	$ 25,884	$ 26,384
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	1	5
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	0	0
Available-for-sale Securities	25,885	26,389
Available for sale Securities Current \| Commercial Paper
Schedule of Available-for-sale Securities
Cost	24,883	13,137
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	0	0
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	0	0
Available-for-sale Securities	24,883	13,137
Available for sale Securities Current \| US Government Agencies Debt Securities [Member]
Schedule of Available-for-sale Securities
Cost	1,001	13,247
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	1	5
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	0	0
Available-for-sale Securities	1,002	13,252
Available For Sale Securities Non Current [Member]
Schedule of Available-for-sale Securities
Cost	2,874	2,507
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	89	0
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	0	3
Available-for-sale Securities	2,963	2,504
Available For Sale Securities Non Current [Member] \| Exchange traded funds and money market securities [Member]
Schedule of Available-for-sale Securities
Cost	2,874	2,507
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	89	0
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	0	3
Available-for-sale Securities	$ 2,963	$ 2,504

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.

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=27724398&loc=d3e27161-111563

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.

+ 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=27724398&loc=d3e27161-111563

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

+ References

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=51813488&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=27724398&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=49167202&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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