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Stockholders' Equity - Authorized and Outstanding Equity (Details) | Mar. 31, 2021 vote $ / shares shares | Dec. 31, 2020 $ / shares shares
--- | --- | ---
Class of Stock [Line Items] |  |
Common stock, shares, outstanding | 79,162,652 | 78,572,110
Restricted Stock |  |
Class of Stock [Line Items] |  |
Unvested - Number of awards (in shares) | 5,407,381 | 5,293,642
Holdings GP Units | Restricted Stock |  |
Class of Stock [Line Items] |  |
Unvested - Number of awards (in shares) | 5,297,254 |
Class A Common Stock |  |
Class of Stock [Line Items] |  |
Common stock, par value per share (in dollars per share) | $ / shares | $ 0.01 | $ 0.01
Common stock, shares authorized (in shares) | 500,000,000 | 500,000,000
Common stock, shares, outstanding | 64,821,842 | 63,131,007
Common stock votes per share | vote | 1 |
Class B Common Stock |  |
Class of Stock [Line Items] |  |
Common stock, par value per share (in dollars per share) | $ / shares | $ 0.01 | $ 0.01
Common stock, shares authorized (in shares) | 200,000,000 | 200,000,000
Common stock, shares, outstanding | 3,783,601 | 4,457,958
Common stock votes per share | vote | 1 |
Class C Common Stock |  |
Class of Stock [Line Items] |  |
Common stock, par value per share (in dollars per share) | $ / shares | $ 0.01 | $ 0.01
Common stock, shares authorized (in shares) | 400,000,000 | 400,000,000
Common stock, shares, outstanding | 10,557,209 | 10,983,145
Common stock votes per share | vote | 1 |

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