Financial Instruments (Details) - USD ($) $ in Thousands	Jun. 29, 2019	Mar. 30, 2019
Available-for-sale securities
Amortized Cost	$ 2,798,548	$ 3,096,631
Gross Unrealized Gains	1,694	893
Gross Unrealized Losses	(6,095)	(17,437)
Estimated Fair Value	2,794,147	3,080,087
Money Market Funds [Member]
Available-for-sale securities
Amortized Cost	585,075	428,150
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	585,075	428,150
Financial institution securities [Member]
Available-for-sale securities
Amortized Cost	509,853	537,795
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	509,853	537,795
Non-financial institution securities [Member]
Available-for-sale securities
Amortized Cost	311,954	702,483
Gross Unrealized Gains	35	3
Gross Unrealized Losses	(176)	(562)
Estimated Fair Value	311,813	701,924
U.S. Government and Agency Securities [Member]
Available-for-sale securities
Amortized Cost	267,414	334,185
Gross Unrealized Gains	49	39
Gross Unrealized Losses	(47)	(139)
Estimated Fair Value	267,416	334,085
Foreign Government and Agency Securities [Member]
Available-for-sale securities
Amortized Cost	399,407	214,455
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	399,407	214,455
Mortgage-Backed Securities [Member]
Available-for-sale securities
Amortized Cost	580,189	684,596
Gross Unrealized Gains	1,524	809
Gross Unrealized Losses	(5,166)	(14,635)
Estimated Fair Value	576,547	670,770
Asset-backed Securities [Member]
Available-for-sale securities
Amortized Cost	50,358	76,852
Gross Unrealized Gains	26	0
Gross Unrealized Losses	(113)	(483)
Estimated Fair Value	50,271	76,369
Commercial Mortgage Backed Securities [Member]
Available-for-sale securities
Amortized Cost	94,298	118,115
Gross Unrealized Gains	60	42
Gross Unrealized Losses	(593)	(1,618)
Estimated Fair Value	$ 93,765	$ 116,539

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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- Definition

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=118939692&loc=d3e27161-111563

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

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