Financial Instruments Investments in Marketable Debt Securities (Tables)

6 Months Ended

Jun. 30, 2020

Cash Equivalents And Marketable Securities [Abstract]

Schedule of Investments in available-for-sale Debt Securities

At June 30, 2020, our investments in available-for-sale debt securities, excluding $1.2 million of corporate debt securities and commercial paper included in cash and cash equivalents, are detailed below (in thousands):

	June 30, 2020
	(Unaudited)
	Amortized Cost		Unrealized Gains		Unrealized Losses		Fair Value
Current:
Corporate debt securities	$	7,920	$	5	$	—	$	7,925
Current portion		7,920		5		—		7,925
Total	$	7,920	$	5	$	—	$	7,925

At December 31, 2019, our investments in available-for-sale debt securities are detailed below (in thousands):

	December 31, 2019
	Amortized Cost		Unrealized Gains		Unrealized Losses			Fair Value
Current:
Corporate debt securities	$	32,382	$	10	$	(3	)	$	32,389
Foreign government bonds		1,007		—		—			1,007
Government sponsored securities		2,752		—		(4	)		2,748
Current portion		36,141		10		(7	)		36,144
Noncurrent:
Corporate debt securities		1,501		—		(4	)		1,497
Noncurrent portion		1,501		—		(4	)		1,497
Total	$	37,642	$	10	$	(11	)	$	37,641

Accumulated Unrealized Losses on Debt Securities Classified as Available-for-Sale in Continuous Loss Position

Accumulated unrealized losses on debt securities classified as available-for-sale that have been in a continuous loss position for less than 12 months and for more than 12 months at June 30, 2020 and December 31, 2019 were as follows (in thousands):

	June 30, 2020
	(Unaudited)
	Less than 12 months				More than 12 months
	Estimated Fair Value		Gross Unrealized Losses		Estimated Fair Value		Gross Unrealized Losses
Corporate debt securities	$	400	$	—	$	—	$	—
Total	$	400	$	—	$	—	$	—

	December 31, 2019
	Less than 12 months					More than 12 months
	Estimated Fair Value		Gross Unrealized Losses			Estimated Fair Value		Gross Unrealized Losses
Corporate debt securities	$	11,021	$	(3	)	$	1,497	$	(4	)
Government sponsored securities		—		—			2,748		(4	)
Total	$	11,021	$	(3	)	$	4,245	$	(8	)