Investments and Fair Value Measurement (Tables)

6 Months Ended

Jun. 30, 2013

Investments and Fair Value Measurement [Abstract]

Schedule of investments

The table below summarizes the Company’s available-for-sale securities (in thousands):

	Amortized Cost		Gross Unrealized Gains		Gross Unrealized (Losses)			Estimated Fair Value
June 30, 2013
Cash equivalents:
Money market funds	$	8,184	$	—	$	—		$	8,184
Total		8,184		—		—			8,184
Available-for-sale securities:
U.S. government sponsored entity debt securities		54,074		—		(1	)		54,073
Total		54,074		—		(1	)		54,073
Total cash equivalents and available-for-sale securities	$	62,258	$	—	$	(1	)	$	62,257
December 31, 2012
Cash equivalents:
U.S. government sponsored entity debt securities	$	2,997	$	—	$	—		$	2,997
Money market funds		15,839		—		—			15,839
Total		18,836		—		—			18,836
Available-for-sale securities:
U.S. government sponsored entity debt securities		54,426		26		—			54,452
Total		54,426		26		—			54,452
Total cash equivalents and available-for-sale securities	$	73,262	$	26	$	—		$	73,288

Summary of fair value measurements of cash equivalents and available-for-sale securities

The fair value measurements of our cash equivalents and available-for-sale marketable securities are identified at the following levels within the fair value hierarchy (in thousands):

	June 30, 2013 Fair Value Measurements
	Total		Level 1		Level 2		Level 3
Assets:
Cash equivalents:
Money market funds	$	8,184	$	8,184	$	—	$	—
Total		8,184		8,184		—		—
Available-for-sale securities:
U.S. government sponsored entity debt securities		54,073		—		54,073		—
Total		54,073		—		54,073		—
Total cash equivalents and available-for-sale securities	$	62,257	$	8,184	$	54,073	$	—
	December 31, 2012 Fair Value Measurements
	Total		Level 1		Level 2		Level 3
Assets:
Cash equivalents:
U.S. government sponsored entity debt securities	$	2,997	$	—	$	2,997	$	—
Money market funds		15,839		15,839		—		—
Total		18,836		15,839		2,997		—
Available-for-sale securities:
U.S. government sponsored entity debt securities		54,452		—		54,452		—
Total		54,452		—		54,452		—
Total cash equivalents and available-for-sale securities	$	73,288	$	15,839	$	57,449	$	—