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Fair Value - Narrative (Detail) - USD ($)
 9 Months Ended
Jan. 30, 2022
Jan. 31, 2021
May 02, 2021
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]      
Short-term investments - available for sale $ 438,000 $ 5,548,000 $ 5,542,000 [1]
Investment remaining maturity period 2 years 3 months 18 days    
Amortized cost of held-to-maturity investments $ 10,000,000.0 10,300,000 4,300,000
Fair value of held-to-maturity investments 9,800,000 10,300,000 4,300,000
Long-term investments (Rabbi Trust) - available for sale 9,223,000 8,232,000 8,415,000 [1]
Short-term Investments [Member]      
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]      
Accumulated unrealized gain (loss) on investments (2,000) 30,000 24,000
Current Expected Credit Loses [Member]      
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]      
Accumulated unrealized gain (loss) on investments (2,000)    
Allowance for credit losses related to short-term available for sale or held-to-maturity investments 0 0 0
Credit loss expense 0 0  
Long-term Investments (Rabbi Trust) [Member]      
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]      
Accumulated unrealized gain (loss) on investments $ 90,000 $ 87,000 $ 122,000
[1] Derived from audited financial statements.