Marketable Securities (Tables)

12 Months Ended

Dec. 31, 2019

Investments, Debt and Equity Securities [Abstract]

Available-for-sale securities

Marketable securities consisted of the following as of December 31, 2019 and 2018:

December 31, 2019	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Money market mutual funds	$	29,907	$	—	$	—	$	29,907
Total marketable securities designated as available-for-sale	$	29,907	$	—	$	—	$	29,907

December 31, 2018	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Money market mutual funds	$	25	$	—	$	—	$	25
Total marketable securities designated as available-for-sale	$	25	$	—	$	—	$	25

Available-for-sale securities, debt maturities, amortized cost and fair value basis

The amortized costs and fair value of debt securities as of December 31, 2019 and 2018 are shown below by effective maturity. Effective maturities may differ from contractual maturities because the issuers of the securities may have the right to prepay obligations without prepayment penalties.

December 31, 2019	Amortized Cost		Fair Value
Due in less than one year	$	—	$	—
December 31, 2018	Amortized Cost		Fair Value
Due in less than one year	$	—	$	—