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Stockholders' Equity Share Activity by Class (Details) - shares | 12 Months Ended |
--- | --- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Class of Stock [Line Items] |  |  |  |
Stock Issued During Period, Shares, New Issues | (1,074) | (24,233) |  |
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation | (177,960) | (126,971) | (82,729) |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number |  | 60,000 |  |
Outstanding | 79,035,069 | 78,572,110 | 77,801,854 | 76,942,872
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number | 327,713 | 304,570 | 297,891 |
Class A Common Stock |  |  |  |
Class of Stock [Line Items] |  |  |  |
Stock Issued During Period, Shares, New Issues | (1,074) | (24,233) |  |
Shares repurchased and retired during the period (shares) | (100,404) |  |  |
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation | (177,960) | (126,971) | (82,729) |
Outstanding | 66,699,872 | 63,131,007 | 56,429,825 | 54,071,188
Class B Common Stock |  |  |  |
Class of Stock [Line Items] |  |  |  |
Stock Issued During Period, Shares, New Issues | (638,614) |  |  |
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation | 0 | 0 | 0 |
Outstanding | 3,206,580 | 4,457,958 | 7,803,364 | 8,645,249
Class C Common Stock |  |  |  |
Class of Stock [Line Items] |  |  |  |
Stock Issued During Period, Shares, New Issues | (325,000) |  |  |
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation | 0 | 0 | 0 |
Outstanding | 9,128,617 | 10,983,145 | 13,568,665 | 14,226,435
Common Stock |  |  |  |
Class of Stock [Line Items] |  |  |  |
Shares repurchased and retired during the period (shares) | (100,404) | (43,091) | (17,289) |
Common Stock | Class A Common Stock |  |  |  |
Class of Stock [Line Items] |  |  |  |
Shares repurchased and retired during the period (shares) |  | (43,091) | (17,289) |
Common Stock | Class B Common Stock |  |  |  |
Class of Stock [Line Items] |  |  |  |
Shares repurchased and retired during the period (shares) | 0 | (32,805) | 0 |
Common Stock | Class C Common Stock |  |  |  |
Class of Stock [Line Items] |  |  |  |
Stock Issued During Period, Shares, New Issues | 0 | (32,805) | 0 |
Follow On Offering [Member] | Class A Common Stock |  |  |  |
Class of Stock [Line Items] |  |  |  |
Stock Issued During Period, Shares, New Issues | (963,614) | (1,802,326) |  |
Follow On Offering [Member] | Class B Common Stock |  |  |  |
Class of Stock [Line Items] |  |  |  |
Stock Issued During Period, Shares, New Issues |  | (1,777,326) |  |
Follow On Offering [Member] | Class C Common Stock |  |  |  |
Class of Stock [Line Items] |  |  |  |
Stock Issued During Period, Shares, New Issues |  | (25,000) |  |
Common Stock | Class A Common Stock |  |  |  |
Class of Stock [Line Items] |  |  |  |
Shares repurchased and retired during the period (shares) |  | (4,128,600) | (1,499,655) |
Common Stock | Class B Common Stock |  |  |  |
Class of Stock [Line Items] |  |  |  |
Shares repurchased and retired during the period (shares) | (612,764) | (1,535,275) | (841,885) |
Common Stock | Class C Common Stock |  |  |  |
Class of Stock [Line Items] |  |  |  |
Shares repurchased and retired during the period (shares) | (1,529,528) | (2,593,325) | (657,770) |
Unvested restricted share-based awards |  |  |  |
Class of Stock [Line Items] |  |  |  |
Stock Issued During Period, Shares, New Issues | (740,249) | (916,085) | (959,000) |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number | 5,245,394 | 5,293,642 | 5,005,422 | 4,678,457
Granted in Period, Number of Shares | 741,555 | 919,455 | 963,000 |
Unvested restricted share-based awards | Class A Common Stock |  |  |  |
Class of Stock [Line Items] |  |  |  |
Stock Issued During Period, Shares, New Issues | (740,249) | (916,085) | (959,000) |
Unvested restricted share-based awards | Class B Common Stock |  |  |  |
Class of Stock [Line Items] |  |  |  |
Shares repurchased and retired during the period (shares) | 0 | 0 | 0 |
Unvested restricted share-based awards | Class C Common Stock |  |  |  |
Class of Stock [Line Items] |  |  |  |
Shares repurchased and retired during the period (shares) | 0 | 0 | 0 |
Performance Shares |  |  |  |
Class of Stock [Line Items] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number | 135,230 | 60,000 | 0 |
Granted in Period, Number of Shares | 75,230 | 60,000 |  |
Performance Shares | Pro Forma |  |  |  |
Class of Stock [Line Items] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number | 135,233 |  |  |

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