The Company has certain assets and liabilities that are measured at fair value on a recurring basis according to a fair value hierarchy that prioritizes the inputs, assumptions and valuation techniques used to measure fair value. The three levels of the fair value hierarchy are:

Level 1—Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities.

Level 2—Quoted prices in markets that are not active or financial instruments for which all significant inputs are observable, either directly or indirectly.

Level 3—Inputs are generally unobservable and reflect management’s estimates of assumptions that market participants would use in pricing the asset or liability. The fair values are determined using model-based techniques, including probability-based simulation methodologies.

The determination of a financial instrument’s level within the fair value hierarchy is based on an assessment of the lowest level of any input that is significant to the fair value measurement. The Company considers observable data to be market data, which is readily available, regularly distributed or updated, reliable and verifiable, not proprietary, and provided by independent sources that are actively involved in the relevant market.

The following tables reflect the Company’s financial asset balances measured on a recurring basis (in thousands):


	March 31, 2022
	Level	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
Cash equivalents:
Money market fund	1	$	71	$	—	$	—		$	71
Commercial paper	2		107,004		5		(6	)		107,003
Total cash equivalents		$	107,075	$	5	$	(6	)	$	107,074
Short-term investments:
Commercial paper	2		57,069		2		(100	)		56,971
U.S. government debt, municipal bonds, and agency securities	2		82,399		—		(603	)		81,796
Corporate bonds	2		6,979		—		(31	)		6,948
Total short-term investments		$	146,447	$	2	$	(734	)	$	145,715
Long-term investments:
Corporate bonds	2		3,305		—		(70	)		3,235
U.S. government debt and agency securities	2		35,062		—		(653	)		34,409
Total long-term investments		$	38,367	$	—	$	(723	)	$	37,644


	December 31, 2021
	Level	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
Cash equivalents:
Money market fund	1	$	57	$	—	$	—		$	57
Commercial paper	2		96,120		—		(5	)		96,115
Total cash equivalents		$	96,177	$	—	$	(5	)	$	96,172
Short-term investments:
Commercial paper	2		74,170		—		(35	)		74,135
U.S. government debt, municipal bonds, and agency securities	2		62,149		2		(59	)		62,092
Corporate bonds	2		7,004		—		(9	)		6,995
Total short-term investments		$	143,323	$	2	$	(103	)	$	143,222
Long-term investments:
Corporate bonds	2		3,307		—		(20	)		3,287
U.S. government debt and agency securities	2		62,911		—		(262	)		62,649
Total long-term investments		$	66,218	$	—	$	(282	)	$	65,936

All the commercial paper, U.S. government debt, municipal bonds and agency securities, U.S. treasury bills, and corporate bonds designated as short-term investments have an effective maturity date that is equal to or less than one year from the respective balance sheet date. Those that are designated as long-term investments have an effective maturity date that is more than one year, but less than two years, from the respective balance sheet date.

The Company evaluated its investments for other-than-temporary impairment and considers the decline in market value for the securities to be primarily attributable to current economic and market conditions. For the investments, it is not more-likely-than-not that the Company will be required to sell the investments, and the Company does not intend to do so prior to the recovery of the amortized cost basis.