Equity-Based Compensation (Successor) (Narrative) (Details) $ in Thousands	11 Months Ended
Dec. 31, 2018 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized under plan (in shares)	50,000,000
Equity-based compensation expense \| $	$ 20,000
Vesting period	3 years
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Option expiration period	7 years
Unrecognized compensation cost \| $	$ 9,800
Period for unrecognized compensation cost	2 years 2 months 9 days
Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost \| $	$ 7,300
Vested restricted stock awards (in shares)	286,214
Granted (shares)	1,720,949
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Unrecognized compensation cost \| $	$ 0
Vested restricted stock awards (in shares)	1,559,749
Granted (shares)	2,049,105
RSUs \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of shares that may be earned	0.00%
RSUs \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of shares that may be earned	200.00%
RSUs \| Tranche one
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rate	20.00%
RSUs \| Tranche two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rate	30.00%
RSUs \| Tranche three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rate	50.00%

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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