Marketable Securities (Tables)

12 Months Ended

Apr. 30, 2021

Investments Debt And Equity Securities [Abstract]

Summary of Fair Value of Company's Investments By Type

The following tables summarize the fair value of the Company’s investments by type as of April 30, 2021 and 2020:

	April 30, 2021
	Amortized		Unrealized		Unrealized			Fair
	Cost		Gains		Losses			Value
Corporate debt securities	$	158,063	$	55	$	(245	)	$	157,873
Obligations of the U.S. Government and its agencies		40,473		7		(16	)		40,464
Total investments	$	198,536	$	62	$	(261	)	$	198,337

	April 30, 2020
	Amortized		Unrealized		Unrealized			Fair
	Cost		Gains		Losses			Value
Corporate debt securities	$	38,922	$	295	$	(1	)	$	39,216
Obligations of the U.S. Government and its agencies		12,534		175		—			12,709
Total investments	$	51,456	$	470	$	(1	)	$	51,925

Summary of Scheduled Maturity for Investments

The following table summarizes the scheduled maturity for the Company’s investments at April 30, 2021:

	April 30,
	2021
Maturing in one year or less	$	129,235
Maturing after one year through two years		50,542
Maturing after two years through four years		18,560
Total investments	$	198,337