Short-Term Investments (Tables)

12 Months Ended

Dec. 31, 2014

Investments, Debt and Equity Securities [Abstract]

Summary of Short-Term Investments

The following table summarizes the Company’s short-term investments (in thousands):

	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Estimated Fair Value
As of December 31, 2014
State, municipal and local government agencies bonds	$	13,946	$	16	$	(1	)	$	13,961
Corporate bonds	17,899		3		(16		)	17,886
Total short-term investments	$	31,845	$	19	$	(17	)	$	31,847
As of December 31, 2013
State, municipal and local government agencies bonds	$	40,426	$	38	$	(15	)	$	40,449
Corporate bonds	33,483		20		(7		)	33,496
Commercial paper	2,299		—		—			2,299
U.S. federal government bonds	4,004		4		—			4,008
Total short-term investments	$	80,212	$	62	$	(22	)	$	80,252

Maturities of Short-Term Investments

The following table summarizes the maturities of the Company’s short-term investments (in thousands):

	December 31,
	2014		2013
Less than one year	$	30,946	$	55,278
Due in 1 - 2 years	901		24,974
Total short-term investments	$	31,847	$	80,252