All investments were considered available-for-sale at September 30, 2022. The amortized cost, gross unrealized holding gains or losses, and fair value of the Company’s investments by major security type at September 30, 2022 and December 31, 2021 are summarized in the table below (in thousands):


	September 30, 2022
	Amortized Cost Basis		Unrealized Gains		Unrealized Losses			Fair Value
Available-for-sale securities:
U.S. treasuries classified as investments	$	120,094	$	6	$	(70	)	$	120,030
Total available-for-sale securities	$	120,094	$	6	$	(70	)	$	120,030


	December 31, 2021
	Amortized Cost Basis		Unrealized Gains		Unrealized Losses			Fair Value
Available-for-sale securities:
U.S. treasuries classified as investments	$	271,570	$	2	$	(156	)	$	271,416
Total available-for-sale securities	$	271,570	$	2	$	(156	)	$	271,416

The amortized cost of available-for-sale securities is adjusted for amortization of premiums and accretion of discounts to maturity. As of September 30, 2022 and December 31, 2021, the aggregate fair value of securities held by the Company in an unrealized loss position for less than twelve months was $85.6 million and $241.4 million, respectively. These securities had remaining maturities of less than one year. The Company has the intent and ability to hold such securities until recovery and has determined that there has been no material change to their credit risk. As a result, the Company determined it did not hold any investments with a credit loss at September 30, 2022 and December 31, 2021.

There were no material realized gains or losses recognized on the sale or maturity of available-for-sale securities during the three and nine months ended September 30, 2022 and 2021, and as a result, there were no material reclassifications out of accumulated other comprehensive gain (loss) for the same periods.