Financial Instruments (Details) - USD ($) $ in Thousands	Jun. 27, 2020	Mar. 28, 2020
Available-for-sale securities
Amortized Cost	$ 2,897,215	$ 2,138,169
Gross Unrealized Gains	2,367	2,699
Gross Unrealized Losses	(649)	(1,052)
Estimated Fair Value	2,898,933	2,139,816
Money Market Funds [Member]
Available-for-sale securities
Amortized Cost	567,333	656,038
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	567,333	656,038
Financial institution securities [Member]
Available-for-sale securities
Amortized Cost	524,980	325,000
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	524,980	325,000
Non-financial institution securities [Member]
Available-for-sale securities
Amortized Cost	505,464	476,735
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(1)	0
Estimated Fair Value	505,463	476,735
U.S. Government and Agency Securities [Member]
Available-for-sale securities
Amortized Cost	549,523	216,178
Gross Unrealized Gains	6	95
Gross Unrealized Losses	(31)	0
Estimated Fair Value	549,498	216,273
Foreign Government and Agency Securities [Member]
Available-for-sale securities
Amortized Cost	595,058	254,283
Gross Unrealized Gains	0	7
Gross Unrealized Losses	(36)	(17)
Estimated Fair Value	595,022	254,273
Mortgage-Backed Securities [Member]
Available-for-sale securities
Amortized Cost	109,067	156,836
Gross Unrealized Gains	2,146	2,445
Gross Unrealized Losses	(319)	(477)
Estimated Fair Value	110,894	158,804
Asset-backed Securities [Member]
Available-for-sale securities
Amortized Cost	868	2,533
Gross Unrealized Gains	16	18
Gross Unrealized Losses	0	(2)
Estimated Fair Value	884	2,549
Commercial Mortgage Backed Securities [Member]
Available-for-sale securities
Amortized Cost	44,922	50,566
Gross Unrealized Gains	199	134
Gross Unrealized Losses	(262)	(556)
Estimated Fair Value	$ 44,859	$ 50,144

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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- References

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27161-111563

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