Marketable Securities - Schedule of Available-for-Sale Securities (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 28, 2014	Mar. 30, 2014
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Amortized Cost	$ 189,646	$ 186,568
Available-for-sale securities, Gross Unrealized Gains	444	543
Available-for-sale securities, Gross Unrealized Losses	(251)	(328)
Available-for-sale securities, Estimated Fair Value	189,839	186,783
U.S. Government and Agency Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Amortized Cost	49,859	49,237
Available-for-sale securities, Gross Unrealized Gains	20	16
Available-for-sale securities, Gross Unrealized Losses	(43)	(55)
Available-for-sale securities, Estimated Fair Value	49,836	49,198
Corporate Debt Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Amortized Cost	72,863	74,386
Available-for-sale securities, Gross Unrealized Gains	133	200
Available-for-sale securities, Gross Unrealized Losses	(70)	(72)
Available-for-sale securities, Estimated Fair Value	72,926	74,514
Mortgage-Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Amortized Cost	33,503	32,778
Available-for-sale securities, Gross Unrealized Gains	176	191
Available-for-sale securities, Gross Unrealized Losses	(109)	(187)
Available-for-sale securities, Estimated Fair Value	33,570	32,782
Other Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Amortized Cost	13,187	5,178
Available-for-sale securities, Gross Unrealized Gains	9	3
Available-for-sale securities, Gross Unrealized Losses	(20)	(5)
Available-for-sale securities, Estimated Fair Value	13,176	5,176
Municipal Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Amortized Cost	20,234	24,989
Available-for-sale securities, Gross Unrealized Gains	106	133
Available-for-sale securities, Gross Unrealized Losses	(9)	(9)
Available-for-sale securities, Estimated Fair Value	$ 20,331	$ 25,113

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)

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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)

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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 210

-SubTopic 10

-Section S99

-Paragraph 1

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-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

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-Section 25

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