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

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Amount of tax benefit from exercise of option under share-based payment arrangement.

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- Definition

Amount of cash inflow from exercise of option under share-based payment arrangement.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Description of terms of share-based payment arrangement. Includes, but is not limited to, type of award or grantee and reason for issuance.

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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

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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.

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No definition available.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

Gross number of share options (or share units) granted during the period.

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No definition available.

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- Definition

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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Share-Based Compensation - Additional Information (Details) $ / shares in Units, $ in Thousands	1 Months Ended	12 Months Ended
	Mar. 31, 2019 $ / shares shares	Dec. 31, 2020 USD ($) Type $ / shares shares	Dec. 31, 2019 USD ($) $ / shares shares	Dec. 31, 2018 USD ($) $ / shares shares	Dec. 31, 2017 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Types of share based awards \| Type		4
Share based awards, description		We currently have four types of share-based awards outstanding to our employees and directors: stock options, restricted stock units, performance-based stock units, and market stock units.
Post-combination expense recognized \| $		$ 14,100	$ 18,800	$ 6,100
Number of shares reserved for future equity grants (in shares)		1,400,000
Total unrecognized compensation cost related to nonvested share-based compensation arrangements granted \| $		$ 14,200
Weighted average period for recognition of unrecognized compensation cost		1 year 7 months 6 days
Stock options granted during period		220,000	0
Total intrinsic value of options exercised during period \| $		$ 600	$ 600	3,900
Cash received from option exercised \| $		1,025	989	1,910
Tax benefit realized from options exercised \| $		$ 200
Total grant-date fair value of shares vested \| $			$ 13,600	$ 23,500	$ 7,600
Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock awards outstanding		0	127,000
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based awards, vesting period		3 years
Stock Options \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based awards, expiration period		7 years
Stock Options \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based awards, expiration period		10 years
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock awards outstanding		1,241,000	393,000
Share based awards, granted		1,774,000
Share based awards, fair value \| $ / shares		$ 11.17	$ 19.68	$ 38.12
Restricted Stock Units (RSUs) \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based awards, vesting period		3 years
Restricted Stock Units (RSUs) \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based awards, vesting period		4 years
Performance-Based Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock awards outstanding		86,000	407,000
Share based awards, granted		4,000		0
Share based awards, fair value \| $ / shares		$ 21.49	$ 20.20
Performance-Based Stock Units \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based awards, vesting period		2 years
Performance-Based Stock Units \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based awards, vesting period		3 years
Market Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock awards outstanding		150,000
Share based awards, vesting period		3 years
Share based awards, granted		150,000	0	0
Share based awards, fair value \| $ / shares		$ 18.84
Time-Vesting Restricted Stock Awards (Replacement Awards) \| Employees \| Nutrisystem
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based awards, granted	258,000
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	919,000
Share based awards, fair value \| $ / shares	$ 19.42
Replacement Awards \| Nutrisystem
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Post-combination expense recognized \| $		$ 900	$ 9,900