MARKETABLE SECURITIES

6 Months Ended

Jun. 30, 2020

Investments, Debt and Equity Securities [Abstract]

Marketable Securities

MARKETABLE SECURITIES

During the three months ended March 31, 2020, the Company changed its investment strategy in response to uncertainties resulting from the COVID-19 pandemic to allow for more flexibility in preserving liquidity. As a result of this change, the classification of the Company's investments changed from held-to-maturity to available-for-sale. The amortized cost of marketable securities transferred from held-to-maturity to available-for-sale was $300.2 million. As a result of the transfer, the Company reversed the allowance for credit loss that had been previously recorded upon adoption of ASU 2016-13 and measured the securities at fair value as of the transfer date by recording an immaterial allowance for credit loss to other income, net, and the remaining adjustment as an immaterial unrealized loss recorded to other comprehensive income.

As a result of its change in investment strategy in March 2020, the Company liquidated its investment portfolio, which consisted of available-for-sale short- and long-term marketable securities, for proceeds of $253.4 million during the six month ended June 30, 2020. The Company recorded an immaterial amount of net realized gains to other income, net and reinvested the proceeds from the sales, along with $73.0 million from maturities and redemptions of marketable securities, into money market funds.

The amortized cost, gross unrealized gains and losses, and fair value of marketable securities classified as held-to-maturity as of December 31, 2019 were as follows (in thousands):

	December 31, 2019
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Short-term marketable securities:
Commercial paper	$	130,464	$	17	$	(9)	$	130,472
Corporate bonds	85,396		225		(10)		85,611
Agency bonds	26,140		90				26,230
Total short-term marketable securities	242,000		332		(19)		242,313
Long-term marketable securities:
Agency bonds	53,499		21		—		53,520
Total long-term marketable securities	53,499		21		—		53,520
Total marketable securities	$	295,499	$	353	$	(19)	$	295,833

The Company did not have any securities that were in an unrealized loss position as of June 30, 2020 due to the liquidation of its investment portfolio. The following table presents gross unrealized losses and fair values for those securities that were in an unrealized loss position as of December 31, 2019, aggregated by investment category and the length of time that the individual securities have been in a continuous loss position (in thousands):

	December 31, 2019
	Less Than 12 Months				12 Months or Greater				Total
	Fair Value		Unrealized Loss		Fair Value		Unrealized Loss		Fair Value		Unrealized Loss
Commercial paper	$	63,639	$	(9)	$	—	$	—	$	63,639	$	(9)
Corporate bonds	20,979		(10)		—		—		20,979		(10)
Total	$	84,618	$	(19)	$	—	$	—	$	84,618	$	(19)

Prior to the adoption of ASU 2016-13, the Company periodically reviewed its investment portfolio for other-than-temporary impairment. The Company considered such factors as the duration, severity and reason for the decline in value, and the potential recovery period. The Company also considered whether it was more likely than not that it would be required to sell the securities before the recovery of their amortized cost basis, and whether the amortized cost basis could not be recovered as a result of credit losses. During the three and six months ended June 30, 2019, the Company did not recognize any other-than-temporary impairment loss