Marketable Securities - Schedule of Available-for-Sale Securities (Detail) - USD ($) $ in Thousands	Dec. 27, 2015	Mar. 29, 2015
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Amortized Cost	$ 212,955	$ 200,579
Available-for-sale securities, Gross Unrealized Gains	134	696
Available-for-sale securities, Gross Unrealized Losses	(684)	(101)
Available-for-sale securities, Estimated Fair Value	212,405	201,174
U.S. Government and Agency Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Amortized Cost	91,312	54,279
Available-for-sale securities, Gross Unrealized Gains	20	173
Available-for-sale securities, Gross Unrealized Losses	(311)	(12)
Available-for-sale securities, Estimated Fair Value	91,021	54,440
Corporate Debt Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Amortized Cost	88,618	99,117
Available-for-sale securities, Gross Unrealized Gains	19	257
Available-for-sale securities, Gross Unrealized Losses	(283)	(51)
Available-for-sale securities, Estimated Fair Value	88,354	99,323
Mortgage-Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Amortized Cost	19,149	26,676
Available-for-sale securities, Gross Unrealized Gains	72	182
Available-for-sale securities, Gross Unrealized Losses	(75)	(36)
Available-for-sale securities, Estimated Fair Value	19,146	26,822
Municipal Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Amortized Cost	12,213	16,647
Available-for-sale securities, Gross Unrealized Gains	23	76
Available-for-sale securities, Gross Unrealized Losses	(10)	(2)
Available-for-sale securities, Estimated Fair Value	12,226	16,721
Other Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Amortized Cost	1,663	3,860
Available-for-sale securities, Gross Unrealized Gains		8
Available-for-sale securities, Gross Unrealized Losses	(5)
Available-for-sale securities, Estimated Fair Value	$ 1,658	$ 3,868

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

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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

+ Details

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This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ 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 (aa)
-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563

Reference 2: 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 investments in debt securities classified as available-for-sale, expected to be converted to cash, sold or exchanged within one year or the normal operating cycle, if longer.

+ 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 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=49167202&loc=d3e26626-111562

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