Fair Value Measurements (Notes)	6 Months Ended
Fair Value Measurements (Notes)	Jun. 30, 2019
Fair Value Disclosures [Abstract]
Fair Value Measurements	12. Fair Value Measurements The carrying amounts 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. The carrying value of the revolving credit facility approximates its fair value. The fair value of the term B loans was $1.0 billion as of June 30, 2019, excluding the $21.0 million of unamortized deferred loan costs (see Note 6. Long-Term Debt) and was determined using Level 1 inputs (quoted prices in active markets for identical assets and liabilities) from the fair value hierarchy. The Company had investments, primarily mutual funds, of $10.8 million and $6.2 million at June 30, 2019 and December 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). Included in selling, general and administrative expenses in the three and six months ended June 30, 2019, is a $3.3 million charge related to management’s decision to no longer use certain foreign trademarks. There were no other fair value adjustments for non-financial assets or liabilities the three and six months ended June 30, 2019 and 2018.

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.