FAIR VALUE MEASUREMENTS

We applied the provisions of the Financial Accounting Standards Board ("FASB") Accounting Standards Codification™ (“ASC”) Topic 820, Fair Value Measurements and Disclosures, for all financial assets and liabilities measured at fair value on a recurring basis. The topic establishes a framework for measuring fair value and requires disclosures about fair value measurements. ASC Topic 820 defines fair value 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 measurement date. The topic establishes market or observable inputs as the preferred sources of values, followed by assumptions based on hypothetical transactions in the absence of market inputs. The topic also establishes a hierarchy for grouping these assets and liabilities based on the significance level of the following inputs, as follows:


•	Level 1—Quoted prices in active markets for identical assets and liabilities.


•	Level 2—Quoted prices in active markets for similar assets and liabilities, quoted prices for identical or similar instruments in markets that are not active, and model‑derived valuations whose inputs are observable or whose significant value drivers are observable.


•	Level 3—Significant inputs to the valuation model are unobservable.

The following is a listing of our assets and liabilities required to be measured at fair value on a recurring basis and where they are classified within the hierarchy as of March 31, 2015, and December 31, 2014 (in thousands):



			Fair Value at Reporting Date Using
	March 31, 2015		Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1)		Significant Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Investments
Corporate bonds	$	44,853	$	—	$	44,853	$	—



			Fair Value at Reporting Date Using
	December 31, 2014		Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1)		Significant Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Investments
Corporate bonds	$	21,288	$	—	$	21,288	$	—

Financial assets or liabilities are categorized within the hierarchy based upon the lowest level of input that is significant to the fair value measurement. Below is a general description of our valuation methodologies for financial assets and liabilities, which are measured at fair value and are included on the condensed consolidated balance sheets.

Our available-for-sale investments consist of corporate bonds that are valued using Level 2 inputs. Market pricing for these investments is obtained from an established financial markets data provider.

The methods described above may result in a fair value estimate that may not be indicative of net realizable value or may not be reflective of future fair values and cash flows. While we believe that the valuation methods used are appropriate and consistent with the requirements of ASC Topic 820 and the methods used by other marketplace participants, we recognize that third parties may use different methodologies or assumptions to determine the fair value of certain financial instruments that could result in a different estimate of fair value at the reporting date.

Financial Instruments—The carrying values and estimated fair values of our financial instruments as of March 31, 2015, and December 31, 2014, are as follows (in thousands):



	March 31, 2015				December 31, 2014
	Carrying Value		Fair Value		Carrying Value		Fair Value
Long-term debt	$	150,000	$	140,000	$	150,000	$	138,000

For cash and cash equivalents, certificate of deposit investments, accounts receivable, refundable income taxes, and accounts payable, the carrying amount approximates fair value because of the short-term maturity of these instruments. The estimated fair value of the long-term debt is estimated using a discounted cash flow analysis based on current borrowing rates for debt with similar remaining maturities and ratings (a Level 2 input) and is designed to approximate the amount at which the instruments could be exchanged in an arm's length transaction between knowledgeable willing parties.