FAIR VALUE OF FINANCIAL INSTRUMENTS

12 Months Ended

Dec. 31, 2017

The Company’s investments in money market accounts are recorded as cash equivalents at fair value in the consolidated financial statements. All other financial instruments are classified as held-to-maturity investments and, accordingly, are recorded at amortized cost; however, the Company is required to determine the fair value of these investments on a recurring basis to identify any potential impairment. The accounting guidance for fair value measurements prioritizes the inputs used in measuring fair value in the following hierarchy:

Level 1—Observable inputs, such as quoted prices in active markets,

Level 2—Inputs other than quoted prices in active markets that are observable either directly or indirectly, or

Level 3—Unobservable inputs in which there are little or no market data, which require the Company to develop its own assumptions.

This hierarchy requires the Company to use observable market data, when available, to minimize the use of unobservable inputs when determining fair value. The Company’s money market funds are classified within Level 1 of the fair value hierarchy because they are valued using quoted prices in active markets. The Company’s commercial paper, corporate bonds, agency bonds and agency discount notes are classified within Level 2 of the fair value hierarchy because they have been valued using inputs other than quoted prices in active markets that are observable directly or indirectly.

The following table represents the fair value of the Company’s financial instruments, including those measured at fair value on a recurring basis and those held-to-maturity as of December 31, 2017 and 2016 (in thousands):



	December 31, 2017								December 31, 2016
	Level 1		Level 2		Level 3		Total		Level 1		Level 2		Level 3		Total
Cash Equivalents:
Money market funds	$	217,838	$	—	$	—	$	217,838	$	152,423	$	—	$	—	$	152,423
Commercial paper	—		46,927		—		46,927		—		—		—		—
Marketable Securities:
Commercial paper	—		138,412		—		138,412		—		45,894		—		45,894
Agency bonds	—		78,913		—		78,913		—		152,394		—		152,394
Corporate bonds	—		69,926		—		69,926		—		9,006		—		9,006
Agency discount notes	—		10,989		—		10,989		—		—		—		—
Total cash equivalents and marketable securities	$	217,838	$	345,167	$	—	$	563,005	$	152,423	$	207,294	$	—	$	359,717

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

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