Stockholders' Equity - Share Activity by Class of Stock (Details) - shares	6 Months Ended
Jun. 30, 2021	Dec. 31, 2020
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (in shares)	78,572,110
Shares issued (in shares)	0
Holdings Common Unit Exchanges (in shares)	(95,235)
Restricted share award net share settlement (in shares)	(176,194)
Delivery of shares underlying RSUs (in shares)	1,074
Ending balance (in shares)	79,042,004
Class A Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (in shares)	63,131,007
Holdings common unit exchanges (in shares)	(274,947)
Holdings Common Unit Exchanges (in shares)	(95,235)
Restricted share award net share settlement (in shares)	(176,194)
Delivery of shares underlying RSUs (in shares)	1,074
Ending balance (in shares)	64,839,462
Class B Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (in shares)	4,457,958
Holdings common unit exchanges (in shares)	(171,811)
Holdings Common Unit Exchanges (in shares)	0
Restricted share award net share settlement (in shares)	0
Delivery of shares underlying RSUs (in shares)	0
Ending balance (in shares)	3,647,533
Class C Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (in shares)	10,983,145
Holdings common unit exchanges (in shares)	(103,136)
Holdings Common Unit Exchanges (in shares)	0
Restricted share award net share settlement (in shares)	0
Delivery of shares underlying RSUs (in shares)	0
Ending balance (in shares)	10,555,009
Restricted Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued (in shares)	(740,249)
Granted (in shares)	741,555
Unvested - Number of awards (in shares)	5,254,784	5,293,642
Restricted Stock \| Class A Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued (in shares)	(740,249)
Restricted Stock \| Class B Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued (in shares)	0
Restricted Stock \| Class C Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued (in shares)	0
Restricted Stock Units RSUs
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Restricted stock units outstanding (in shares)	328,310	304,570
Granted (in shares)	1,306
Performance Shares
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued in period (in shares)	135,230
Granted (in shares)	75,230
Unvested - Number of awards (in shares)	135,230	60,000
Performance Shares \| Potential Performance Shares
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Unvested - Number of awards (in shares)	165,233
Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Holdings Common Unit Exchanges (in shares)	0
Follow On Offering
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued (in shares)	0
Follow On Offering \| Class A Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued (in shares)	(963,614)
Follow On Offering \| Class B Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued (in shares)	(638,614)
Follow On Offering \| Class C Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued (in shares)	(325,000)

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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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 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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Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

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Number of shares issued under share-based payment arrangement.

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Number of shares used to settle grantee's tax withholding obligation for award under share-based payment arrangement.

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The number of shares issued during the period upon the conversion of units. An example of a convertible unit is an umbrella partnership real estate investment trust unit (UPREIT unit).

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Number of shares issued in lieu of cash for services contributed to the entity. Number of shares includes, but is not limited to, shares issued for services contributed by vendors and founders.

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Number of new stock issued during the period.

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Number of shares that have been repurchased and retired during the period.

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