Restricted Cash (Details) - USD ($) $ in Thousands	Jan. 25, 2020	Apr. 27, 2019	Jan. 26, 2019	Apr. 28, 2018
Cash and Cash Equivalents [Abstract]
Cash and cash equivalents	$ 166,272	$ 129,819	$ 101,579
Restricted cash	1,973	1,968	2,003
Total cash, cash equivalents and restricted cash	$ 168,245	$ 131,787	$ 103,582	$ 136,871

Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as current. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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Name:	us-gaap_RestrictedCashAndCashEquivalentsAtCarryingValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant