Investments

12 Months Ended

Dec. 31, 2020

Investments, All Other Investments [Abstract]

Investments in Privately-Held Companies

Our investments in privately-held companies do not have readily determinable fair values. Their initial cost is subsequently adjusted to fair value on a non-recurring basis based on observable price changes from orderly transactions of identical or similar securities of the same issuer or for impairment. These investments are classified within Level III of the fair value hierarchy as we estimate the value based on valuation methods using the observable transaction price at the transaction date and other significant unobservable inputs, such as volatility, rights, and obligations related to these securities. In addition, the valuation requires management judgment due to the absence of market price and lack of liquidity. The following table summarizes the activity related to our investments in privately-held companies held as of December 31, 2020 and 2019 (in thousands):


	December 31, 2020		December 31, 2019
Cost of investment	$	3,000	$	3,000
Cumulative impairment	—		—
Cumulative upward adjustment	5,314		1,150
Carrying amount of investment	$	8,314	$	4,150

During the year ended December 31, 2019, we recorded a realized gain of $4.3 million upon the sale of one of our investments. In each of the years ended December 31, 2020, 2019 and 2018, we recorded $4.2 million, $1.2 million and $1.2 million of unrealized gains, respectively. These unrealized gains were recorded on investments that were re-measured to fair value as of the date observable transactions occurred. In addition, during the year ended December 31, 2018, we recorded an impairment of $15.0 million on one of our disposed investments. The aforementioned realized and unrealized gains and impairment were recorded within other income, net in the accompanying consolidated statements of operations.