XML 42 R31.htm IDEA: XBRL DOCUMENT v3.23.1
Real Estate - Text (Detail) - USD ($)
$ in Millions
3 Months Ended 6 Months Ended
Mar. 31, 2023
Mar. 31, 2022
Mar. 31, 2023
Mar. 31, 2022
Sep. 30, 2022
Real Estate Properties [Line Items]          
Real estate $ 1,988.0   $ 1,988.0   $ 2,022.4
Payments to Acquire Residential Real Estate     47.2    
Payments to Develop Real Estate Assets     374.4    
Real Estate Carrying Value 35.5   35.5    
Asset Impairment Charges   $ 3.8      
Due Diligence Write-Offs 0.9 $ 1.6 3.3 $ 2.2  
Inventory Write-down     19.4    
Developed and under development projects          
Real Estate Properties [Line Items]          
Real estate 1,920.4   1,920.4   1,932.6
Land held for future development          
Real Estate Properties [Line Items]          
Real estate $ 67.6   $ 67.6   $ 89.8
D.R. Horton, Inc. [Member] | Maximum          
Real Estate Properties [Line Items]          
Related Party Transaction, Rate     16.00%    
D.R. Horton, Inc. [Member] | Minimum          
Real Estate Properties [Line Items]          
Related Party Transaction, Rate     12.00%