Stock-Based Compensation - Summary of Vested Performance Based and Time Based Restricted Stock Units (Detail) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
		May 03, 2020	Apr. 28, 2019	Apr. 29, 2018
Time Based Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted Stock Units Vested		0	1,200	1,200
Weighted Average Fair Value	[1]	$ 0	$ 21	$ 37
Price Per Share	[2]	$ 0	$ 17.36	$ 30.90
Performance Based Restricted Stock Units [Member] | Key Employees and Senior Executives [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted Stock Units Vested	[3]	11,351	128,632	102,845
Weighted Average Fair Value	[1],[3]	$ 197	$ 3,754	$ 3,342
Price Per Share	[3]	$ 17.36	$ 29.19	$ 32.50
Performance Based Restricted Stock Units [Member] | Non-employee [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted Stock Units Vested	[4]	4,961	10,364	16,000
Weighted Average Fair Value	[1],[4]	$ 86	$ 320	$ 520
Price Per Share	[4]	$ 17.36	$ 30.90	$ 32.50

[1] Dollar amounts are in thousands.

[2] Price per share represents closing price of our common stock on the date the respective award vested.

[3] Certain senior executives and key employees.

[4] Non-employee