Fair Value Measurements - Investments (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2018	Apr. 01, 2017
Available for sale Securities Current
Schedule of Available-for-sale Securities
Available-for-sale Securities	$ 55,118	$ 10,688
Unrealized Gain	0	0
Unrealized Loss	(36)	0
Cost	55,154	10,688
Available for sale Securities Current \| US Treasury Securities [Member]
Schedule of Available-for-sale Securities
Available-for-sale Securities	12,958
Unrealized Gain	0
Unrealized Loss	(17)
Cost	12,975
Available for sale Securities Current \| Commercial Paper
Schedule of Available-for-sale Securities
Available-for-sale Securities	29,411	10,688
Unrealized Gain	0	0
Unrealized Loss	0	0
Cost	29,411	10,688
Available for sale Securities Current \| Corporate Bonds
Schedule of Available-for-sale Securities
Available-for-sale Securities	12,749
Unrealized Gain	0
Unrealized Loss	(19)
Cost	12,768
Available for sale Securities Non Current
Schedule of Available-for-sale Securities
Available-for-sale Securities	2,048	3,058
Unrealized Gain	167	84
Unrealized Loss	0	0
Cost	1,881	2,974
Available for sale Securities Non Current \| Exchange Traded Funds [Member]
Schedule of Available-for-sale Securities
Available-for-sale Securities	2,048
Unrealized Gain	167
Unrealized Loss	0
Cost	$ 1,881
Available for sale Securities Non Current \| Municipal Bonds
Schedule of Available-for-sale Securities
Available-for-sale Securities		3,058
Unrealized Gain		84
Unrealized Loss		0
Cost		$ 2,974

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=75030427&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=82897076&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=82896770&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
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=82897076&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
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