Fair Value Measurements - Investments (Details) - USD ($) $ in Thousands	12 Months Ended
Apr. 02, 2016	Mar. 28, 2015
Available for sale Securities Current
Schedule of Available-for-sale Securities
Available-for-sale Securities	$ 26,389	$ 25,039
Unrealized Gain	5	127
Unrealized Loss	0	0
Cost	26,384	24,912
Available for sale Securities Current \| Commercial Paper
Schedule of Available-for-sale Securities
Available-for-sale Securities	13,137	15,537
Unrealized Gain	0	0
Unrealized Loss	0	0
Cost	13,137	15,537
Available for sale Securities Current \| Government agencies
Schedule of Available-for-sale Securities
Available-for-sale Securities	13,252	2,702
Unrealized Gain	5	0
Unrealized Loss	0	0
Cost	13,247	2,702
Available for sale Securities Current \| Corporate Bonds
Schedule of Available-for-sale Securities
Available-for-sale Securities		853
Unrealized Gain		0
Unrealized Loss		0
Cost		853
Available for sale Securities Current \| Mutual, Exchange Traded, and Money Market funds [Member]
Schedule of Available-for-sale Securities
Available-for-sale Securities		2,075
Unrealized Gain		125
Unrealized Loss		0
Cost		1,950
Available for sale Securities Current \| Municipal Bonds
Schedule of Available-for-sale Securities
Available-for-sale Securities		3,872
Unrealized Gain		2
Unrealized Loss		0
Cost		$ 3,870
Available for sale Securities Non Current
Schedule of Available-for-sale Securities
Available-for-sale Securities	2,504
Unrealized Gain	0
Unrealized Loss	(3)
Cost	2,507
Available for sale Securities Non Current \| Exchange Traded Funds [Member]
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)
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+ 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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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)
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