Marketable Securities (Tables)

12 Months Ended

Apr. 30, 2020

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, 2020 and 2019:

	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

	April 30, 2019
	Amortized		Unrealized		Unrealized			Fair
	Cost		Gains		Losses			Value
Corporate debt securities	$	56,083	$	405	$	(1	)	$	56,487
Obligations of the U.S. Government and its agencies		12,282		36		—			12,318
Total investments	$	68,365	$	441	$	(1	)	$	68,805

Summary of Scheduled Maturity for Investments

The following table summarizes the scheduled maturity for the Company’s investments at April 30, 2020:

	April 30,
	2020
Maturing in one year or less	$	32,391
Maturing after one year through two years		11,698
Maturing after two years		7,836
Total investments	$	51,925