Marketable Securities (Tables)

9 Months Ended

Sep. 30, 2020

Investments, Debt and Equity Securities [Abstract]

Schedule for available-for-sale securities

The following is a summary of available-for-sale securities as of September 30, 2020 (in thousands):

	Amortized Cost		Gross Unrealized Gain		Gross Unrealized (Losses)		Estimated Fair Value
Corporate debt securities	$	22,865	$	485	$	—	$	23,350
Tax-exempt municipal securities	21,907		275		(12)		22,170
Variable rate demand notes	5,600		—		—		5,600
Total	$	50,372	$	760	$	(12)	$	51,120

The following is a summary of available-for-sale securities as of December 31, 2019 (in thousands):

	Amortized Cost		Gross Unrealized Gain		Gross Unrealized (Losses)		Estimated Fair Value
Corporate debt securities	$	42,584	$	165	$	(40)	$	42,709
Tax-exempt municipal securities	23,301		112		(215)		23,198
Variable rate demand notes	5,600		—		—		5,600
Total	$	71,485	$	277	$	(255)	$	71,507

Schedule of maturities of marketable securities

The following table summarizes the maturities of the Company’s marketable securities as of December 31, 2019 and September 30, 2020 (in thousands):

	December 31, 2019		September 30, 2020
Due within one year	$	34,874	$	20,457
Due after one year through five years	36,633		30,663
Total	$	71,507	$	51,120

Schedule of proceeds from the maturities of available-for-sale securities

The following table summarizes the proceeds from the maturities and sales of available-for-sale securities for the three and nine months ended September 30, 2019 and 2020 (in thousands):

	For the three months ended September 30,				For the nine months ended September 30,
	2019		2020		2019		2020
Maturities of marketable securities	$	10,300	$	3,999	$	32,860	$	21,404
Sales of marketable securities	—		—		—		1,464
Total	$	10,300	$	3,999	$	32,860	$	22,868