Fair Value of Financial Instruments	6 Months Ended
Fair Value of Financial Instruments	Jun. 30, 2016
Fair Value Disclosures [Abstract]
Fair Value of Financial Instruments	Fair Value of Financial Instruments At June 30, 2016 and December 31, 2015, the carrying amounts of cash equivalents, accounts payable and accrued liabilities approximate fair value because of their short-term nature. The fair value of the convertible notes, which differs from their carrying value, is influenced by interest rates and stock price and stock price volatility and is determined by prices for the convertible notes observed in market trading. The market for trading of the convertible notes is not considered to be an active market and therefore the estimate of fair value is based on Level 2 inputs. The estimated fair value of the convertible notes, face value of $200.0 million, was $214.0 million at June 30, 2016 and $198.0 million at December 31, 2015, respectively.

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.