Marketable Securities - Schedule of Available-for-Sale Securities (Detail) - USD ($) $ in Thousands	Sep. 27, 2015	Mar. 29, 2015
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Amortized Cost	$ 205,495	$ 200,579
Available-for-sale securities, Gross Unrealized Gains	520	696
Available-for-sale securities, Gross Unrealized Losses	(196)	(101)
Available-for-sale securities, Estimated Fair Value	205,819	201,174
U.S. Government and Agency Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Amortized Cost	75,175	54,279
Available-for-sale securities, Gross Unrealized Gains	222	173
Available-for-sale securities, Gross Unrealized Losses	(8)	(12)
Available-for-sale securities, Estimated Fair Value	75,389	54,440
Corporate Debt Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Amortized Cost	89,321	99,117
Available-for-sale securities, Gross Unrealized Gains	89	257
Available-for-sale securities, Gross Unrealized Losses	(143)	(51)
Available-for-sale securities, Estimated Fair Value	89,267	99,323
Mortgage-Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Amortized Cost	22,683	26,676
Available-for-sale securities, Gross Unrealized Gains	151	182
Available-for-sale securities, Gross Unrealized Losses	(42)	(36)
Available-for-sale securities, Estimated Fair Value	22,792	26,822
Municipal Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Amortized Cost	14,238	16,647
Available-for-sale securities, Gross Unrealized Gains	52	76
Available-for-sale securities, Gross Unrealized Losses	(3)	(2)
Available-for-sale securities, Estimated Fair Value	14,287	16,721
Other Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Amortized Cost	4,078	3,860
Available-for-sale securities, Gross Unrealized Gains	6	8
Available-for-sale securities, Estimated Fair Value	$ 4,084	$ 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

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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.

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

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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

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