Investments

9 Months Ended

Sep. 30, 2021

Cash And Cash Equivalents [Abstract]

Investments

Note C - Investments

Cash equivalents and short-term investments consisted of the following as of September 30, 2021 and December 31, 2020 (in thousands):

	September 30, 2021				December 31, 2020
	Cost		Estimated Fair Value		Cost		Estimated Fair Value
Institutional money market funds	$	227,798	$	227,798	$	64,256	$	64,256
U.S. Treasury Bills		19,997		19,997		20,000		20,000
Total	$	247,795	$	247,795	$	84,256	$	84,256

As a result of the short-term nature of our investments, there were minimal unrealized holding gains or losses for the three and nine months ended September 30, 2021 and 2020.

Of the investments listed above, $242.8 million were classified as cash equivalents and $5.0 million as short-term investments on our condensed consolidated balance sheets as of September 30, 2021. All were classified as cash equivalents as of December 31, 2020.