Fair Value Measurement (Details) - USD ($) $ in Thousands	Feb. 01, 2020	Apr. 27, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available-for-sale securities:	$ 1,727	$ 26,344
Certificates of deposit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available-for-sale securities:	1,727	3,464
U.S. Government securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available-for-sale securities:		10,774
U.S. Government sponsored entities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available-for-sale securities:		10,482
Municipal bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available-for-sale securities:		1,624
Reported Value Measurement [Member] \| Recurring Basis
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cash and cash equivalents	40,316	35,383
Restricted cash	60	359
Derivatives - asset position	50	91
Derivatives - liability position	(227)	(4)
Acquisition-related contingent consideration	(729)	(3,065)
Assets (Liabilities), net	41,197	59,108
Reported Value Measurement [Member] \| Recurring Basis \| Certificates of deposit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available-for-sale securities:	1,727	3,464
Reported Value Measurement [Member] \| Recurring Basis \| U.S. Government securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available-for-sale securities:		10,774
Reported Value Measurement [Member] \| Recurring Basis \| U.S. Government sponsored entities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available-for-sale securities:		10,482
Reported Value Measurement [Member] \| Recurring Basis \| Municipal bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available-for-sale securities:		1,624
Estimate of Fair Value Measurement [Member] \| Recurring Basis \| Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cash and cash equivalents	40,316	35,383
Restricted cash	60	359
Derivatives - asset position	0	0
Derivatives - liability position	0	0
Acquisition-related contingent consideration	0	0
Assets (Liabilities), net	40,376	46,516
Estimate of Fair Value Measurement [Member] \| Recurring Basis \| Level 1 \| Certificates of deposit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available-for-sale securities:	0	0
Estimate of Fair Value Measurement [Member] \| Recurring Basis \| Level 1 \| U.S. Government securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available-for-sale securities:		10,774
Estimate of Fair Value Measurement [Member] \| Recurring Basis \| Level 1 \| U.S. Government sponsored entities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available-for-sale securities:		0
Estimate of Fair Value Measurement [Member] \| Recurring Basis \| Level 1 \| Municipal bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available-for-sale securities:		0
Estimate of Fair Value Measurement [Member] \| Recurring Basis \| Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cash and cash equivalents	0	0
Restricted cash	0	0
Derivatives - asset position	50	91
Derivatives - liability position	(227)	(4)
Acquisition-related contingent consideration	0	0
Assets (Liabilities), net	1,550	15,657
Estimate of Fair Value Measurement [Member] \| Recurring Basis \| Level 2 \| Certificates of deposit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available-for-sale securities:	1,727	3,464
Estimate of Fair Value Measurement [Member] \| Recurring Basis \| Level 2 \| U.S. Government securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available-for-sale securities:		0
Estimate of Fair Value Measurement [Member] \| Recurring Basis \| Level 2 \| U.S. Government sponsored entities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available-for-sale securities:		10,482
Estimate of Fair Value Measurement [Member] \| Recurring Basis \| Level 2 \| Municipal bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available-for-sale securities:		1,624
Estimate of Fair Value Measurement [Member] \| Recurring Basis \| Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Cash and cash equivalents	0	0
Restricted cash	0	0
Derivatives - asset position	0	0
Derivatives - liability position	0	0
Acquisition-related contingent consideration	(729)	(3,065)
Assets (Liabilities), net	(729)	(3,065)
Estimate of Fair Value Measurement [Member] \| Recurring Basis \| Level 3 \| Certificates of deposit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available-for-sale securities:	$ 0	0
Estimate of Fair Value Measurement [Member] \| Recurring Basis \| Level 3 \| U.S. Government securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available-for-sale securities:		0
Estimate of Fair Value Measurement [Member] \| Recurring Basis \| Level 3 \| U.S. Government sponsored entities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available-for-sale securities:		0
Estimate of Fair Value Measurement [Member] \| Recurring Basis \| Level 3 \| Municipal bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Available-for-sale securities:		$ 0

Restricted Cash and Cash Equivalents, Fair Value Disclosure

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

+ References

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- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
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-Topic 805
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Fair value of asset after deduction of liability.

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Fair value portion of asset contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward contracts, and swaps.

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Fair value portion of liability contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward (delivery or nondelivery) contracts, and swaps entered into.

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