Marketable Securities (Narrative) (Details) $ in Thousands	9 Months Ended
Dec. 26, 2020 USD ($) security	Mar. 28, 2020 USD ($) security
Debt Securities, Available-for-sale [Line Items]
Amortized cost on available for sale securities held at gross unrealized loss	$ 8,300	$ 172,900
Securities in a continuous unrealized loss position for more than 12 months, number of securities \| security	0	0
Gross unrealized losses	$ 11	$ 3,993
Minimum
Debt Securities, Available-for-sale [Line Items]
Maturity period for highly-rated securities	1 year
Maximum
Debt Securities, Available-for-sale [Line Items]
Maturity period for highly-rated securities	3 years

Amortized cost of available for sale securities in an unrealized loss position.

No definition available.

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- Definition

Debt Securities, Available-For-Sale, Maturity Period

+ References

No definition available.

+ Details

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- Definition

Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (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 (c)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27161-111563

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- Definition

Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without an allowance for credit loss. Includes beneficial interest in securitized financial asset.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 50
-Paragraph 4
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=121582814&loc=SL82922888-210455

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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