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Joint Ventures and Variable Interest Entities - Schedule of Equity in Earnings of Unconsolidated Joint Ventures (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024
Joint Ventures and Variable Interest Entities [Line Items] |  |  |  |
Total | $ 5,290 | $ 7,647 | $ 21,707 | $ (1,835)
Unconsolidated Joint Ventures |  |  |  |
Joint Ventures and Variable Interest Entities [Line Items] |  |  |  |
Total |  |  | 21,700 | (1,800)
Unconsolidated Joint Ventures | Pass-through joint ventures |  |  |  |
Joint Ventures and Variable Interest Entities [Line Items] |  |  |  |
Total |  |  | 21,600 | 24,700
Unconsolidated Joint Ventures | Other joint ventures |  |  |  |
Joint Ventures and Variable Interest Entities [Line Items] |  |  |  |
Total |  |  | $ 100 | $ (26,500)

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