Investments - Available-for-Sale (Details) - USD ($) $ in Thousands	Jul. 01, 2018	Apr. 01, 2018
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 270,336
Estimated Fair Value	198,188	$ 222,026
U.S. government treasuries and agencies securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	61,184	61,166
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(896)	(894)
Estimated Fair Value	60,288	60,272
Money market funds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	26,979	48,847
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	26,979	48,847
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	15,958	16,797
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(93)	(110)
Estimated Fair Value	15,865	16,687
Corporate bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	111,135	111,266
Gross Unrealized Gains	37	43
Gross Unrealized Losses	(1,690)	(1,704)
Estimated Fair Value	109,482	109,605
International government bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,650	2,650
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(6)	(12)
Estimated Fair Value	2,644	2,638
Corporate commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	10,683	9,034
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	10,683	9,034
Bank deposits
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	41,456	45,080
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	41,456	45,080
Repurchase agreements
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	291	142
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	291	142
Total available-for-sale investments
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	270,336	294,982
Gross Unrealized Gains	37	43
Gross Unrealized Losses	(2,685)	(2,720)
Estimated Fair Value	267,688	292,305
Less amounts classified as cash equivalents
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	69,500	70,279
Gross Unrealized Gains	0	0
Gross Unrealized Losses	0	0
Estimated Fair Value	69,500	70,279
Short-term investments
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	200,836	224,703
Gross Unrealized Gains	37	43
Gross Unrealized Losses	(2,685)	(2,720)
Estimated Fair Value	$ 198,188	$ 222,026

Amount, before tax, of unrealized gain 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).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
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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).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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-Name Accounting Standards Codification
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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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