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The number of shares converted in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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

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Unrecognized cost of unvested options awarded to employees as compensation.

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Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

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Share-Based Compensation - Narrative (Details) $ / shares in Units, $ in Thousands		6 Months Ended
	May 23, 2018	Jun. 30, 2018 USD ($) $ / shares shares	Jun. 30, 2017 USD ($)	May 24, 2018 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share-based compensation expense \| $		$ 2,851	$ 1,574
Compensation not yet recognized, stock options, nonvested awards \| $		$ 7,900
Award requisite service period (in years)		4 years 1 month 6 days
Stock split, conversion ratio	10
Unvested HoldCo Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award requisite service period (in years)		4 years 4 days
Compensation not yet recognized, nonvested awards \| $		$ 17,700
Unvested Class A stock awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award requisite service period (in years)		4 years 4 months 2 days
Compensation not yet recognized, nonvested awards \| $		$ 1,500
Profits Interests converted into vested and unvested HoldCo Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares converted as part of the Reorganization Transaction (in shares)		15,241,530
Price per share (in dollars per share) \| $ / shares		$ 23.00
Profits Interests converted into vested and unvested HoldCo Units \| Vested HoldCo Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of new shares converted from Profit Interests (in shares)		2,941,139
Profits Interests converted into vested and unvested HoldCo Units \| Unvested HoldCo Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of new shares converted from Profit Interests (in shares)		3,172,843
Profits Interests converted into vested and unvested Class A stock awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares converted as part of the Reorganization Transaction (in shares)		940,000
Price per share (in dollars per share) \| $ / shares		$ 23.00
Profits Interests converted into vested and unvested Class A stock awards \| Vested Class A stock awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of new shares converted from Profit Interests (in shares)		127,327
Profits Interests converted into vested and unvested Class A stock awards \| Unvested Class A stock awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of new shares converted from Profit Interests (in shares)		255,904
Class A common stock \| 2018 Omnibus Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)				24,000,000