Revenue (Details) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2023 |
Jun. 30, 2022 |
Jun. 30, 2023 |
Jun. 30, 2022 |
|
| Revenue from External Customer [Line Items] | ||||
| Deferred development lot sales | $ 10.3 | $ 7.9 | $ 24.6 | $ 20.4 |
| Tract sales and other | 23.8 | 5.5 | 68.2 | 9.1 |
| Revenues | 368.9 | 308.5 | 887.1 | 1,137.7 |
| Real Estate | Residential Real Estate [Member] | ||||
| Revenue from External Customer [Line Items] | ||||
| Revenue from Contract with Customer, Including Assessed Tax | $ 334.8 | $ 295.1 | $ 794.3 | $ 1,108.2 |