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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) |

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