Fair Value Measurements

6 Months Ended

Jun. 30, 2019

The carrying amount of cash and cash equivalents, restricted cash, receivables, prepaid expenses and other current assets, accounts payable, accrued compensation and benefits, other accrued liabilities, and related party payables approximate fair value due to the short maturity of these instruments.

Assets

The following table presents the placement in the fair value hierarchy of financial assets that are measured at fair value on a recurring basis, including the items for which the fair value option has been elected, at June 30, 2019:



	Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		June 30, 2019
Assets
U.S. government debt securities	$	—	$	67,301	$	—	$	67,301
Equity securities	1,196		266		20,041		21,503
Other	—		468		247		715
Total	$	1,196	$	68,035	$	20,288	$	89,519



	Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		December 31, 2018
Assets
U.S. government debt securities	$	—	$	119,340	$	—	$	119,340
Equity securities	1,626		556		—		2,182
Other	—		468		191		659
Total	$	1,626	$	120,364	$	191	$	122,181

The method used to estimate the fair value of the Level 1 assets in the tables above is based on observable market data as these equity securities are publicly-traded. The method used to estimate the fair value of the Level 2 short-term investments in the tables above is based on professional pricing sources for identical or comparable instruments, rather than direct observations of quoted prices in active markets. The methods used to estimate the fair value of the Level 2 and Level 3 equity securities in the tables above are based on the quoted market price of the publicly-traded security, adjusted for any trading restrictions, including discounts for lack of marketability based on historical volatilities and the restriction period. Market price volatility of these Level 3 securities and a significant change in the assumptions used in the discount for lack of marketability could result in a significant impact to the fair value. The Company owns preferred stock in certain of its collaborators, and these investments are classified as Level 3 within the fair value hierarchy. The methods used to estimate the fair value of these Level 3 assets are discussed in Note 17.

The following table summarizes the changes in the Level 3 investments in equity securities and preferred stock during the six months ended June 30, 2019.



	Six Months Ended June 30, 2019
Beginning balance	$	191
Retained interest in deconsolidated subsidiary	14,239
Dividend income from investments in preferred stock	25
Net unrealized appreciation in the fair value of the investments in equity securities and preferred stock	5,833
Ending balance	$	20,288

There were no transfers of assets between levels of the fair value hierarchy during the six months ended June 30, 2019.

Liabilities

The carrying values of the Company's long-term debt, excluding the 3.50% convertible senior notes due 2023 (the "Convertible Notes"), approximates fair value due to the length of time to maturity and/or the existence of interest rates that approximate prevailing market rates.

The calculated fair value of the Convertible Notes (Note 11) was approximately $112,000 and $141,000 as of June 30, 2019 and December 31, 2018, respectively, and is based on the most recent third-party trade of the instrument as of the balance sheet date. The fair value of the Convertible Notes is classified as Level 2 within the fair value hierarchy as there is not an active market for the Convertible Notes, however, third-party trades of the instrument are considered observable inputs. The Convertible Notes are reflected on the accompanying consolidated balance sheets at amortized cost, which was $152,634 and $148,101 as of June 30, 2019 and December 31, 2018, respectively.

The Company's contingent consideration liabilities are measured on a recurring basis and were $585 at June 30, 2019 and December 31, 2018. These fair value measurements were based on significant inputs not observable in the market and thus represented a Level 3 measurement. A significant change in unobservable inputs could result in a significant impact on the fair

value of the Company's contingent consideration liabilities. The contingent consideration liabilities are remeasured to fair value at each reporting date until the contingencies are resolved, and those changes in fair value are recognized in earnings. There were no changes in the fair value of the Level 3 liabilities during the three and six months ended June 30, 2019.

- 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.

+ References + Details