Cash, Cash Equivalents and Short-Term Investments (Tables)

12 Months Ended

Dec. 31, 2014

Cash and Cash Equivalents [Abstract]

Summary of Cash, Cash Equivalents and Short-Term Investments

Cash, cash equivalents and short-term investments consist of the following (in thousands):

	As of December 31, 2014
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Cash and cash equivalents:
Cash	$	26,284	$	—	$	—	$	26,284
Bank deposits		11,877		—		—		11,877
Commercial paper		18,341		—		2		18,339
Money market funds		11,596		—		—		11,596
Total	$	68,098	$	—	$	2	$	68,096
Short-term investments:
Corporate debt obligations	$	31,404	$	3	$	53	$	31,354
Bank deposits		10,270		—		—		10,270
Total	$	41,674	$	3	$	53	$	41,624

	As of December 31, 2013
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Cash and cash equivalents:
Cash	$	41,973	$	—	$	—	$	41,973
Bank deposits		10,165		—		—		10,165
Commercial paper		21,948		—		1		21,947
Money market funds		2,619		—		—		2,619
Total	$	76,705	$	—	$	1	$	76,704
Short-term investments:
Corporate debt obligations	$	28,220	$	22	$	14	$	28,228
Bank deposits		10,153		—		—		10,153
Total	$	38,373	$	22	$	14	$	38,381

Summary of Cost and Estimated Fair Value of Short-Term Investments

The following table sets forth the cost and estimated fair value of short-term investments based on stated effective maturities as of December 31, 2014 (in thousands):

	As of December 31, 2014
			Estimated
	Amortized		Fair
	Cost		Value
Short-term investments:
Due within one year	$	28,891	$	28,888
Due within two years		12,783		12,736
Total	$	41,674	$	41,624

Schedule of Short-Term Investments at Fair Value and Length of Continuous Unrealized Loss Position

The following tables show the short-term investments in an unrealized loss position and the related gross unrealized losses and fair value and length of time that the short-term investments have been in a continuous unrealized loss position (in thousands):

	As of December 31, 2014
	Less than 12 Months				12 Months or Greater				Total
	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
Corporate debt obligations	$	12,735	$	47	$	12,088	$	6	$	24,823	$	53
	As of December 31, 2013
	Less than 12 Months				12 Months or Greater				Total
	Fair Value		Unrealized Losses		Fair Value		Unrealized Losses		Fair Value		Unrealized Losses
Corporate debt obligations	$	8,394	$	14	$	—	$	—	$	8,394	$	14