Short-term Investments

6 Months Ended

Jun. 30, 2015

Short-term Investments [Abstract]

Short-term Investments

(2)  Short-term Investments

Short-term investments, classified as available for sale, are stated at fair value. Determination of the fair values of each short-term investment is further discussed in Note (3) below.

As of June 30, 2015, the fair value of the Company’s short-term investments was as follows (in thousands):

	June 30, 2015
	Amortized cost		Unrealized gains		Unrealized loss		Fair value
	(unaudited)
U.S. agency notes	$	36,617	$	4	$	(3)	$	36,618
Corporate bonds		36,998		1		(31)		36,968
Commercial paper		24,794		2		—		24,796
Marketable securities		98,409		7		(34)		98,382
Certificates of deposit		7,000		—		—		7,000
Total short-term investments	$	105,409	$	7	$	(34)	$	105,382

As of December 31, 2014, the fair value of the Company’s short-term investments was as follows (in thousands):

		December 31, 2014
	Amortized cost		Unrealized gains		Unrealized loss		Fair value
U.S. agency notes	$	33,489	$	—	$	(13)	$	33,476
Corporate bonds		44,025		3		(44)		43,984
Commercial paper		31,318		—		(1)		31,317
Marketable securities		108,832		3		(58)		108,777
Certificates of deposit		3,000		—		—		3,000
Total short-term investments	$	111,832	$	3	$	(58)	$	111,777

The Company considers any declines in the market value of its marketable securities to be temporary in nature and does not consider any of its investments other-than-temporarily impaired. When evaluating an investment for other-than-temporary impairment, the Company reviews factors such as the length of time and extent to which fair value has been below its cost basis, the financial condition of the issuer, changes in market interest rates, the Company’s intent to sell, and/or whether it is more likely than not that the Company will be required to sell the investment before recovery of the investment’s cost basis. During the periods presented, the Company did not recognize any other-than-temporary impairment charges. The maturity period of the Company’s available for sale securities is within one year.