Stock-Based Compensation - Expense (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jan. 25, 2020	Jan. 26, 2019	Jan. 25, 2020	Jan. 26, 2019
Stock-based compensation expense recognized for outstanding grants
Equity-based awards expense	$ 2,528	$ 2,495	$ 7,235	$ 8,174
Liability-based awards expense	(303)	144	37	10
Total stock-based compensation expense	$ 2,225	$ 2,639	$ 7,272	$ 8,184

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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