Short-term investments, principally U.S. Treasury bills, are available-for-sale and consisted of the following (in thousands):


	As of March 31, 2024
	Amortized Cost		Unrealized Loss, Net			Estimated Fair Value
U.S. Treasury securities	$	92,745	$	(36	)	$	92,709


	As of December 31, 2023
	Amortized Cost		Unrealized Gain, Net		Estimated Fair Value
U.S. Treasury securities	$	117,480	$	10	$	117,490

All available-for-sale securities held as of March 31, 2024 and December 31, 2023 had a maturity of less than one year. The Company has classified all marketable securities, regardless of maturity, as short-term investments based upon the Company’s ability and intent to use any and all of those marketable securities to satisfy the Company’s liquidity requirements.