Owned Inventory - Impairment Charges Taken on Land Held for Sale (Details) $ in Thousands	12 Months Ended
	Sep. 30, 2025 USD ($) lot community	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)
Inventory [Line Items]
# of Communities Impaired | community	4
# of Lots Impaired | lot	131
Impairment Charge	$ 2,733	$ 0	$ 0
Level 3 | Fair Value, Measurements, Nonrecurring
Inventory [Line Items]
Estimated Fair Value Less Cost to Sell of Impaired Inventory at Time of Impairment	$ 11,240
Operating Segments | West
Inventory [Line Items]
# of Communities Impaired | community	4
# of Lots Impaired | lot	131
Impairment Charge	$ 1,495	0	0
Operating Segments | West | Level 3 | Fair Value, Measurements, Nonrecurring
Inventory [Line Items]
Estimated Fair Value Less Cost to Sell of Impaired Inventory at Time of Impairment	$ 11,240
Corporate and unallocated
Inventory [Line Items]
# of Communities Impaired | community	0
# of Lots Impaired | lot	0
Impairment Charge	$ 1,238	$ 0	$ 0
Corporate and unallocated | Level 3 | Fair Value, Measurements, Nonrecurring
Inventory [Line Items]
Estimated Fair Value Less Cost to Sell of Impaired Inventory at Time of Impairment	$ 0