Fair Value Measurements (Notes)	3 Months Ended
Fair Value Measurements (Notes)	Mar. 31, 2018
Fair Value Disclosures [Abstract]
Fair Value Measurements	7. Fair Value Measurements The carrying values of cash and cash equivalents, accounts receivable, accounts payable and accrued payroll and contractor professional pay approximate their fair value based on their short-term nature. Long-term debt recorded in the Company’s condensed consolidated balance sheet at March 31, 2018 was $565.9 million (net of $12.1 million of unamortized deferred loan costs, refer to "Note 5. Long-Term Debt"). The fair value of the term B loan was determined using Level 1 inputs (quoted prices in active markets for identical assets and liabilities) from the fair value hierarchy. The fair value of the term B loan was $582.3 million as of March 31, 2018. The Company had investments, primarily mutual funds, of $3.3 million at March 31, 2018, held in a rabbi trust restricted to fund the Company's deferred compensation plan. The fair value of these investments was determined using Level 1 inputs from the fair value hierarchy. These assets are included in other non-current assets. Certain assets and liabilities, such as goodwill and trademarks, are not measured at fair value on an ongoing basis but are subject to fair value adjustments in certain circumstances (e.g., when there is evidence of impairment). For the three months ended March 31, 2018 or 2017, no fair value adjustments were required for non-financial assets or liabilities.

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.