Fair Value Measurements

12 Months Ended

Dec. 31, 2019

Fair Value Disclosures [Abstract]

FAIR VALUE MEASUREMENTS

5. FAIR VALUE MEASUREMENTS

The Company’s financial instruments consist of cash and cash equivalents, short-term investments, restricted cash and accounts payable. The carrying amount of cash, restricted cash and accounts payable are each considered a reasonable estimate of fair value due to the short-term maturity.

Assets measured at fair value on a recurring basis were as follows:

Description	December 31, 2019		Quoted Prices (Unadjusted) in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
	(in thousands)
Cash equivalents:
Money market mutual funds	$	39,524	$	39,524	$	—	$	—
Repurchase agreements		14,000		—		14,000		—
Total cash equivalents	$	53,524	$	39,524	$	14,000	$	—
Short-term investments:
Asset-backed securities	$	14,876	$	—	$	14,876	$	—
Commercial paper		41,259		—		41,259		—
U.S. Treasury securities		59,971		—		59,971		—
Corporate debt securities		92,508		—		92,508		—
Total short-term investments	$	208,614	$	—	$	208,614	$	—
Total financial assets	$	262,138	$	39,524	$	222,614	$	—

Description	December 31, 2018		Quoted Prices (Unadjusted) in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
	(in thousands)
Cash equivalents:
Money market mutual funds	$	31,740	$	31,740	$	—	$	—
Commercial paper		5,974		—		5,974		—
U.S. Treasury securities		35		35		—		—
Total cash equivalents	$	37,749	$	31,775	$	5,974	$	—
Short-term investments:
Asset-backed securities	$	19,520	$	—	$	19,520	$	—
U.S. Treasury securities		29,939		—		29,939		—
Corporate debt securities		54,461		—		54,461		—
Commercial paper		72,597		—		72,597		—
Total short-term investments	$	176,517	$	—	$	176,517	$	—
Total financial assets	$	214,266	$	31,775	$	182,491	$	—

Short-term securities are valued using models or other valuation methodologies that use Level 2 inputs. These models are primarily industry-standard models that consider various assumptions, including time value, yield curve, volatility factors, default rates, current market and contractual prices for the underlying financial instruments, as well as other relevant economic measures. Substantially all of these assumptions are observable in the marketplace, can be derived from observable data or are supported by observable levels at which transactions are executed in the marketplace.

There were no transfers between fair value measure levels during the years ended December 31, 2019 and 2018.