Fair Value Measurements

6 Months Ended

Jun. 30, 2017

Fair Value Disclosures [Abstract]

Fair Value Measurements

3. Fair Value Measurements

Financial assets and liabilities are recorded at fair value. The accounting guidance for fair value provides a framework for measuring fair value, clarifies the definition of fair value and expands disclosures regarding fair value measurements. Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability (an exit price) in an orderly transaction between market participants at the reporting date. The accounting guidance establishes a three-tiered hierarchy, which prioritizes the inputs used in the valuation methodologies in measuring fair value as follows:

Level 1—Inputs are unadjusted, quoted prices in active markets for identical assets or liabilities at the measurement date.

Level 2—Inputs other than quoted market prices included in Level 1 are either directly or indirectly observable for the asset or liability through correlation with market data at the measurement date and for the duration of the instrument’s anticipated life.

Level 3—Inputs reflect management’s best estimate of what market participants would use in pricing the asset or liability at the measurement date. Consideration is given to the risk inherent in the valuation technique and the risk inherent in the inputs to the model.

The following table sets forth the Company’s financial instruments that were measured at fair value on a recurring basis by level within the fair value hierarchy (in thousands):

	Fair Value Measurements at June 30, 2017
	Total		Level 1		Level 2		Level 3
Assets
Money market funds	$	116,328	$	116,328	$	—	$	—
U.S. government agency obligations		31,984		—		31,984		—
Corporate securities		16,013		—		16,013		—
Total	$	164,325	$	116,328	$	47,997	$	—
	Fair Value Measurements at December 31, 2016
	Total		Level 1		Level 2		Level 3
Assets
Money market funds	$	136,481	$	136,481	$	—	$	—
U.S. government agency obligations		12,075		—		12,075		—
Corporate securities		3,999		—		3,999		—
Total	$	152,555	$	136,481	$	16,074	$	—

The following table is a summary of amortized cost, unrealized gain and loss, and fair value (in thousands) of the Company’s marketable securities by contractual maturities:

	Fair Value Measurements at June 30, 2017
	Amortized Cost		Unrealized Gain		Unrealized Loss			Fair Value
Cash equivalents (due within 90 days)	$	116,328	$	—	$	—		$	116,328
Short-term investments (due within one year)		16,031		—		(20	)	$	16,011
Long-term investments (due between one and two years)		32,011		6		(31	)	$	31,986
Total	$	164,370	$	6	$	(51	)	$	164,325
	FairValue Measurements at December 31, 2016
	Amortized Cost		Unrealized Gain		Unrealized Loss			Fair Value
Cash equivalents (due within 90 days)	$	136,481	$	—	$	—		$	136,481
Short-term investments (due within one year)		4,072		—		—			4,072
Long-term investments (due between one and two years)		11,988		14		—			12,002
Total	$	152,541	$	14	$	—		$	152,555