Fair Value Measurements

Fair value of financial instruments

The carrying amounts of financial instruments, including cash, cash equivalents and restricted cash, accounts receivable, accounts payable and accrued expenses, approximate fair value due to the short maturity of these instruments. Accordingly, these instruments are not presented in the table below. The following table provides the estimated fair values of the remaining financial instruments:



	As of March 31, 2020				As of December 31, 2019
(in thousands)	Carrying Value		Fair Value		Carrying Value		Fair Value
Financial Instruments:
Highview Investment	$	552	$	552	$	552	$	552
Highview Obligation	$	208	$	208	$	220	$	220

Concentration of credit risk

The Company's financial instruments that are exposed to concentrations of credit risk consist primarily of cash and cash equivalents. The Company holds cash and cash equivalents at three financial institutions as of March 31, 2020. If an institution was unable to perform its obligations, the Company would be at risk regarding the amount of cash and investments in excess of the Federal Deposit Insurance Corporation limits (currently $250 thousand) that would be returned to the Company.

Assets and Liabilities Measured at Fair Value on a Recurring Basis

As of March 31, 2020 and December 31, 2019, the Company had no financial instruments carried and measured at fair value on a recurring basis.

Assets and Liabilities Measured at Fair Value on a Non-Recurring Basis

As disclosed in Note 2, the Company completed the Carbon Solutions Acquisition for purchase consideration of $66.5 million. The estimated fair values of the assets acquired and liabilities assumed were determined based on Level 3 inputs.

The Company has applied the measurement alternative for investments without readily determinable fair values under ASC Topic 321 - Investments in Equity Securities ("ASC 321") for the Highview Investment. Fair value measurements, if any, resulting from the Company's application of the guidance in ASC 321 represent either Level 2 or Level 3 measurements. There were no changes to the carrying value of the Highview Investment for the three months ended March 31, 2020 and 2019 as there were no indicators of impairment or observable price changes for identical or similar investments.