Fair Value Measurements	6 Months Ended
Fair Value Measurements	Jun. 30, 2014
Fair Value Measurements [Abstract]
Fair Value Measurements	(4) Fair Value Measurements Our financial instruments include cash and cash equivalents, accounts receivable, non‑marketable securities, accounts payable, a term loan and certain accrued liabilities. The carrying amounts of our cash and cash equivalents (which are comprised primarily of deposit and overnight sweep accounts), accounts receivable, accounts payable, and certain accrued liabilities approximate fair value due to the short maturity of these instruments. The estimated fair values of the non-marketable equity securities have been determined from information obtained from independent valuations and management estimates. The carrying value of our long-term debt recognized in the consolidated balance sheets as of June 30, 2014 and December 31, 2013, was approximately $230,955 and $236,432, respectively, while the fair value of long-term debt as of June 30, 2014 and December 31, 2013, was approximately $235,000 and $226,789, respectively based on Level 2 inputs consisting of quoted market prices for the same issues or quoted market prices for similar issues in active markets. See note 6 for further discussion of our debt. Non-Current Investments At June 30, 2014, we held equity securities in two private companies, which are classified within other assets in our condensed consolidated balance sheets. The investments in these equity securities are classified as Level 3 investments and are accounted for using the equity method of accounting. Any losses due to impairment in value are recorded as realized losses when such losses occur. The carrying value of these Level 3 investments at June 30, 2014 and December 31, 2013, is $453.

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