Tax Receivable Agreement Liability	6 Months Ended
Tax Receivable Agreement Liability	Jun. 30, 2018
Income Tax Disclosure [Abstract]
Tax Receivable Agreement Liability	Tax Receivable Agreement Liability In connection with the IPO, the Company entered into a tax receivable agreement ("TRA") with Parent 2 that provides for the payment by the Company to Parent 2 of 90% of the amount of cash savings, if any, in U.S. federal, state, local and non-U.S. income tax that the Company realizes (or in some circumstances are deemed to realize) as a result of the utilization of the Company and the Company’s subsidiaries’ (i) depreciation and amortization deductions, and any offset to taxable income and gain or increase to taxable loss, resulting from the tax basis the Company has in its assets at the consummation of the IPO, (ii) net operating losses, (iii) tax credits and (iv) certain other tax attributes. During the three months ended March 31, 2017, the Company recorded a liability of $203.8 million, with a corresponding offset to additional paid-in capital for the TRA. At the end of each reporting period, any changes in the Company's estimate of the liability are recorded in the consolidated statement of operations as a component of other income (expense). The timing and amount of future tax benefits associated with the TRA are subject to change, and future payments may be required which could be materially different from the current estimated liability. The TRA will remain in effect until all tax benefits have been used or expired, unless the agreement is terminated early. During the three months ended December 31, 2017, the Company recorded a gain in other income of $68.0 million due to the federal income tax rate being reduced from 35.0% to 21.0% as part of the Tax Act. As of June 30, 2018, and December 31, 2017, the TRA liability balance was $135.8 million. There have been no payments related to the TRA from inception to June 30, 2018. The first payment related to the TRA is anticipated to be made during the fourth quarter of 2018 and is estimated to be $15.9 million and is reflected as a current liability as of June 30, 2018 and December 31, 2017. Income Taxes For the three and six months ended June 30, 2018, the Company's effective tax rates were 29.7% and 24.3%, respectively. The variance from the statutory federal tax rate of 21.0% for the three months ended June 30, 2018 was primarily due to state income taxes, non-deductible items and a foreign rate differential. The variance from the statutory federal rate of 21.0% for the six months ended June 30, 2018 was primarily due to state income taxes, non-deductible items and a foreign rate differential, offset by a refinement of the provisional estimate of the one-time repatriation tax under the Tax Act, treated as a discrete item during the first quarter. For the three and six months ended June 30, 2017, the Company's effective tax rates were 40.6% and 39.8%. The variance from the statutory federal tax rate of 35.0% for both periods was primarily due to state income taxes and non-deductible items. On January 1, 2018, the Company adopted ASU 2018-02, Income Statement-Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income. As a result of income tax effects of the Tax Act, which reduced the corporate federal tax rate from 35.0% to 21.0%, the Company reclassified $0.2 million from accumulated other comprehensive income to retained earnings related to its net investment hedge. On December 22, 2017, the United States government enacted the Tax Act resulting in significant modifications to existing law. The Company follows the guidance in Securities and Exchange Commission Staff Accounting Bulletin ("SAB") 118, which provides additional clarification regarding the application of ASC Topic 740 in situations where the Company does not have the necessary information available, prepared, or analyzed in reasonable detail to complete the accounting for certain income tax effects of the Tax Act for the reporting period in which the Tax Act was enacted. SAB 118 provides for a measurement period beginning in the reporting period that includes the Tax Act’s enactment date and ending when the Company has obtained, prepared, and analyzed the information needed in order to complete the accounting requirements but in no circumstance should the measurement period extend beyond one year from the enactment date. As of June 30, 2018, the Company has completed the accounting for the effects of the Tax Act except for the repricing of ending deferred taxes due to the reduction in the corporate tax rate and the impact of the one-time deemed repatriation transition tax on unrepatriated foreign earnings. As a result, the Company's financial statements reflect these effects of the Tax Act as provisional based on a reasonable estimate of the income tax effects. As of December 31, 2017, the Company had included a provisional reduction in deferred tax liability and corresponding provisional reduction in tax provision expense of $9.1 million in relation to the repricing of its ending deferred tax balance. The provisional amount was and is based on information currently available at that time, including estimated book to tax adjustments. As of June 30, 2018, the Company continues to gather and analyze information, including any future legislative tax developments at the federal or state jurisdictions, in order to complete the accounting for the repricing of the ending deferred balances. The Company has also included a provisional income tax payable in the amount of $0.2 million related to the one-time deemed repatriation transition tax on unrepatriated foreign earnings. The provisional amount is based on information currently available, including estimated tax earnings and profits and tax pools from foreign investments. In addition, the income tax payable has been calculated by electing out of the use of net operating losses in order to maximize the use of foreign tax credits. The Company has also estimated the state tax impact of the Tax Act. The Company continues to gather and analyze information, including historical adjustments to earnings and profits of foreign subsidiaries and the available elections, in order to complete the accounting for the effects of the estimated transition tax. Any future legislative tax developments at the federal or state jurisdictions will need to be examined for potential application. It is the intention of the Company to complete the necessary analysis within the measurement period. The Company considers the earnings of non-U.S. subsidiaries to be indefinitely invested outside the United States based on estimates that future domestic cash generation will be sufficient to meet future domestic cash needs and the Company's specific plans for reinvestment of those subsidiary earnings. As required by the Tax Act, as of June 30, 2018 and December 31, 2017, the Company has recorded a provisional tax liability related to the U.S. federal income taxes of approximately $8.2 million and $10.2 million, respectively, of undistributed earnings of foreign subsidiaries indefinitely invested outside the United States. However, the Company has not recorded a deferred tax liability for state and foreign withholding taxes associated with the repatriation of those foreign earnings. If the Company decides to repatriate the foreign earnings, it would need to adjust its income tax provision in the period it determined that the earnings will no longer be indefinitely invested outside the United States. The Company has no present intention to repatriate any of its foreign earnings.