MARKETABLE SECURITIES (Tables)

3 Months Ended

Mar. 31, 2020

Investments, Debt and Equity Securities [Abstract]

Schedule of the Fair Value to Amortized Cost Basis of Securities Held-to-Maturity

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

Schedule of Securities in an Unrealized Loss Position

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)