Available-for-Sale Securities

9 Months Ended

Sep. 30, 2019

Investments Debt And Equity Securities [Abstract]

Available-for-Sale Securities

4. Available-for-Sale Securities

The following table is a summary of available-for-sale securities recorded in cash and cash equivalents or marketable securities in our condensed consolidated balance sheets (in thousands):

	September 30, 2019
	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
Financial Assets
Money market funds	$	20,230	$	—	$	—		$	20,230
U.S. Treasury securities		4,995		3		—			4,998
Commercial paper		15,091		9		(4	)		15,096
Corporate debt securities		17,190		10		—			17,200
U.S. agency bonds		27,560		25		(1	)		27,584
Total	$	85,066	$	47	$	(5	)	$	85,108

	December 31, 2018
	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
Financial Assets
Money market funds	$	23,156	$	—	$	—		$	23,156
U.S. Treasury securities		25,698		—		(6	)		25,692
Commercial paper		19,203		—		(13	)		19,190
Corporate debt securities		20,449		4		(2	)		20,451
U.S. agency bonds		17,921		—		(4	)		17,917
Total	$	106,427	$	4	$	(25	)	$	106,406

The Company believes that the individual unrealized losses represent temporary declines primarily resulting from interest rate changes, and intends to hold these marketable securities to their maturities.

As of September 30, 2019, the amortized cost and estimated fair value of the Company’s available-for-sale securities by contractual maturity are shown below (in thousands):

	Amortized		Estimated
	Cost		Fair Value
Marketable securities maturing:
In one year or less	$	64,836	$	64,878
Total marketable securities	$	64,836	$	64,878