A savings certificate entitling the Entity (that is, bearer) to receive interest at an established maturity date, based upon a fixed interest rate. A certificate of deposit may be issued in any denomination. Certificates of deposit are generally issued by commercial banks and, therefore, insured by the FDIC (up to the prescribed limit). Certificates of deposit generally restrict holders from withdrawing funds on demand without the incurrence of penalties. Generally, only certificates of deposit with original maturities of three months or less qualify as cash equivalents. Original maturity means original maturity to the entity holding the investment. As a related example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

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Fair Value Measurements - Additional Information (Details) - USD ($)		12 Months Ended
	Nov. 27, 2017	Jan. 31, 2021	Apr. 30, 2021
Derivative [Line Items]
Certificates of deposit			$ 50,000,000
November 2017 Facility \| Secured Debt
Derivative [Line Items]
Debt instrument, principal amount	$ 350,000,000.0
November 2017 Facility \| Secured Debt \| Wells Fargo Bank
Derivative [Line Items]
Debt instrument maturity date	Jul. 12, 2022
November 2017 Facility \| Revolving Credit Facility \| Secured Debt \| Wells Fargo Bank
Derivative [Line Items]
Total debt outstanding with carrying amount		$ 30,000,000.0	30,000,000.0
0.00% Convertible Notes Due 2026 \| Senior Notes
Derivative [Line Items]
Debt instrument interest rate stated percentage		0.00%
Debt instrument maturity date		Jan. 15, 2026
Debt instrument, principal amount		$ 345,000,000.0
0.00% Convertible Notes Due 2026 \| Senior Notes \| Level 2
Derivative [Line Items]
Convertible senior notes, fair value		$ 348,400,000	$ 375,300,000