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Equity - Schedule of Movement in Outstanding Shares of Class A Common Stock, Restricted Class A Common Stock and Deferred Stock Units (Detail) - shares | 1 Months Ended | 9 Months Ended
--- | --- | ---
May 31, 2013 | Sep. 30, 2025 | Sep. 30, 2024
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |
Beginning balance (in shares) |  | 173,204,190 | 173,569,397
Issuance of class A common stock (in shares) | 25,875,000 | 1,778 |
Repurchase of class A common stock (in shares) |  | (2,653,583) | (628,884)
Issuance of restricted class A common stock, net (in shares) |  | 467,180 | 401,901
Issuance of deferred stock units (in shares) |  | 32,165 | 42,338
Ending balance (in shares) |  | 171,051,730 | 173,389,399
Shares forfeited (in shares) |  | 43,832 | 102,484
Director |  |  |
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |
Issuance of restricted class A common stock, net (in shares) |  | 29,140 | 41,282
Deferred Stock Units |  |  |
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |
Number of shares of restricted class A common stock outstanding (in shares) |  | 331,611 | 401,802

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