Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 26, 2020	Mar. 28, 2020
Available-for-sale securities
Amortized Cost	$ 2,956,056	$ 2,138,169
Gross Unrealized Gains	2,219	2,699
Gross Unrealized Losses	(454)	(1,052)
Estimated Fair Value	2,957,821	2,139,816
Money Market Funds [Member]
Available-for-sale securities
Amortized Cost	385,263	656,038
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	385,263	656,038
Financial institution securities [Member]
Available-for-sale securities
Amortized Cost	405,834	325,000
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	405,834	325,000
Non-financial institution securities [Member]
Available-for-sale securities
Amortized Cost	671,987	476,735
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	671,987	476,735
U.S. Government and Agency Securities [Member]
Available-for-sale securities
Amortized Cost	775,394	216,178
Gross Unrealized Gains	51	95
Gross Unrealized Losses	(4)	0
Estimated Fair Value	775,441	216,273
Foreign Government and Agency Securities [Member]
Available-for-sale securities
Amortized Cost	599,862	254,283
Gross Unrealized Gains	0	7
Gross Unrealized Losses	(1)	(17)
Estimated Fair Value	599,861	254,273
Mortgage-Backed Securities [Member]
Available-for-sale securities
Amortized Cost	97,500	156,836
Gross Unrealized Gains	2,017	2,445
Gross Unrealized Losses	(257)	(477)
Estimated Fair Value	99,260	158,804
Asset-backed Securities [Member]
Available-for-sale securities
Amortized Cost	857	2,533
Gross Unrealized Gains	18	18
Gross Unrealized Losses	0	(2)
Estimated Fair Value	875	2,549
Commercial Mortgage Backed Securities [Member]
Available-for-sale securities
Amortized Cost	19,359	50,566
Gross Unrealized Gains	133	134
Gross Unrealized Losses	(192)	(556)
Estimated Fair Value	$ 19,300	$ 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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