Cash, cash equivalents, short-term investments, and restricted cash

9 Months Ended

Sep. 30, 2017

Cash and Cash Equivalents [Abstract]

Cash, cash equivalents, short-term investments and restricted cash

Cash, cash equivalents, short-term investments, and restricted cash

The following table summarizes the Company’s cash, cash equivalents, short-term investments and restricted cash (in thousands):

	September 30, 2017		December 31, 2016
Cash and cash equivalents:
Cash	$	53,716	$	58,691
Cash equivalents	4,812		23,809
Cash and cash equivalents	$	58,528	$	82,500
Short-term investments	$	12,281	$	19,015
Restricted cash	$	2,917	$	4,085

As of September 30, 2017 and December 31, 2016, restricted cash included approximately $2.0 million pursuant to an asset purchase agreement with Optoelectronics Components Co., Ltd. (“APAT OE”) relating to the asset sale closed in January 2017, in addition to the compensating balances relating to the Company’s notes payable issued under its line of credit facilities in China. See Note 8. The following table summarizes the Company’s unrealized gains and losses related to its cash equivalents and short-term investments in marketable securities designated as available-for-sale (in thousands):

	As of September 30, 2017									As of December 31, 2016
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Loss			Fair Value		Amortized Cost		Gross Unrealized Gains		Gross Unrealized Loss			Fair Value
Marketable securities:
Money market funds	$	11,530	$	—	$	—		$	11,530	$	199	$	—	$	—		$	199
Money market accounts	4,812		—		—			4,812		23,809		—		—			23,809
Corporate debt securities	—		—		—			—		9,438		4		(3		)	9,439
Government agency securities	—		—		—			—		3,767		—		(10		)	3,757
U.S. government securities	753		—		(2		)	751		5,008		—		(10		)	4,998
Sovereign government bonds	—		—		—			—		622		—		—			622
Total	$	17,095	$	—	$	(2	)	$	17,093	$	42,843	$	4	$	(23	)	$	42,824
Reported as:
Cash equivalents	$	4,812	$	—	$	—		$	4,812	$	23,809	$	—	$	—		$	23,809
Short-term investments	12,283		—		(2		)	12,281		19,034		4		(23		)	19,015
Total	$	17,095	$	—	$	(2	)	$	17,093	$	42,843	$	4	$	(23	)	$	42,824

As of September 30, 2017 and December 31, 2016, maturities of marketable securities were as follows (in thousands):

	September 30, 2017		December 31, 2016
Less than 1 year	$	17,093	$	36,054
Due in 1 to 2 years	—		6,468
Due in 3 to 5 years	—		302
Total	$	17,093	$	42,824

Realized gains and losses on the sale of marketable securities during the three and nine months ended September 30, 2017 and 2016 were insignificant. The Company did not recognize any impairment losses on its marketable securities during the three and nine months ended September 30, 2017 or 2016. As of September 30, 2017, the Company did not have any investments in marketable securities that were in an unrealized loss position for a period in excess of 12 months.