Inventory - Impairments and Lot Option Abandonment Charges, by Reportable Segment (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Real Estate, Write-down or Reserve [Line Items]
Total impairment and abandonment charges	$ 1,007	$ 450
Continuing Operations
Real Estate, Write-down or Reserve [Line Items]
Impairment charges on projects in progress	1,007	0
Discontinued Operations
Real Estate, Write-down or Reserve [Line Items]
Land Held for Sale	0	450
Southeast Segment | Continuing Operations
Real Estate, Write-down or Reserve [Line Items]
Impairment charges on projects in progress	858	0
Corporate and unallocated | Continuing Operations
Real Estate, Write-down or Reserve [Line Items]
Impairment charges on projects in progress	$ 149	$ 0