Share-Based Compensation - Additional Information (Details) $ / shares in Units, $ in Millions	3 Months Ended
Mar. 31, 2019 USD ($) Type $ / shares shares	Mar. 31, 2018 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Types of share based awards \| Type	5
Share based awards, desription	We currently have five types of share-based awards outstanding to our employees and directors: stock options, restricted stock awards, restricted stock units, performance stock units, and market stock units.
Share-based compensation costs \| $	$ 2.4	$ 1.4
Restructuring and Related Charges
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation costs \| $	$ 0.1
Time-Vesting Restricted Stock Awards (Replacement Awards)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based awards, granted \| shares	258,000
Share based awards, fair value \| $ / shares	$ 19.42
Time-Vesting Restricted Stock Awards (Replacement Awards) \| Employees \| Nutrisystem
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based awards, granted \| shares	258,000
Share based awards, fair value \| $ / shares	$ 19.42
Time-Vesting Restricted Stock Units (Replacement Awards)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based awards, granted \| shares	919,000
Share based awards, fair value \| $ / shares	$ 19.42
Time-Vesting Restricted Stock Units (Replacement Awards) \| Employees \| Nutrisystem
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based awards, granted \| shares	919,000
Share based awards, fair value \| $ / shares	$ 19.42
Replacement Awards \| Nutrisystem
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of replacement awards attributable to pre-combination service \| $	$ 9.1
Post-combination expense expected to be recognized \| $	$ 13.7
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Each of share based awards, vesting period	3 years
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Each of share based awards, vesting period	4 years

Represents the number of types of share-based awards outstanding to employees and directors.

No definition available.

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- Definition

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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- Definition

Fair value at acquisition-date of the equity interest in the acquiree held by the acquirer, immediately before the acquisition date for businesses combined in stages.

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- Definition

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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- Definition

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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- Definition

General descriptive information regarding an arrangement under which employees and directors receive: (a) awards of equity shares, equity share options, or other equity instruments; or (b) the entity incurs liabilities to them: (1) in amounts based, at least in part, on the price of the entity's shares or other equity instruments; or (2) that require or may require settlement by issuance of the entity's shares. Such an arrangement is usually provided to employees and directors to compensate them, provide performance incentives to them, and to attract or retain their services. May also include pertinent information particular to a plan that is not elsewhere specified in the taxonomy.

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- Definition

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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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued 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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- Definition

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.

+ References

No definition available.

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