Fair Value Measurements - Investments (Details) - Available for sale Securities Current - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Sep. 26, 2015	Mar. 28, 2015
Schedule of Available-for-sale Securities
Cost	$ 29,194	$ 24,912
Unrealized Gain	6	127
Unrealized Loss	0	0
Fair Value	(29,200)	(27,114)
Commercial Paper
Schedule of Available-for-sale Securities
Cost	14,728	15,537
Unrealized Gain	0	0
Unrealized Loss	0	0
Fair Value	(14,728)	(15,537)
Government agencies
Schedule of Available-for-sale Securities
Cost	12,146	2,702
Unrealized Gain	1	0
Unrealized Loss	0	0
Fair Value	(12,147)	(2,702)
Mutual Funds and Exchange Traded Funds [Member]
Schedule of Available-for-sale Securities
Cost	2,320	1,950
Unrealized Gain	5	125
Unrealized Loss	0	0
Fair Value	$ (2,325)	(2,075)
Corporate Bond Securities [Member]
Schedule of Available-for-sale Securities
Cost		853
Unrealized Gain		0
Unrealized Loss		0
Fair Value		853
Municipal Bonds
Schedule of Available-for-sale Securities
Cost		3,870
Unrealized Gain		2
Unrealized Loss		0
Fair Value		$ (3,872)

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

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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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.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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

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