Income Taxes - Textual (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021
Operating Loss Carryforwards [Line Items]
Effective tax rate	24.10%	22.70%	21.80%
Federal statutory rate	21.00%	21.00%	21.00%
Net operating loss carryforwards	$ 42.2	$ 44.1
Deferred Tax Assets, Valuation Allowance	14.8	$ 17.9
Home Building | State [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	11.9
Home Building | State [Member] | NOL Carryforwards to Expire in One to Ten Years [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards, subject to expiration	4.5
Home Building | State [Member] | NOL Carryforward to Expire in Eleven to Twenty Years [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards, subject to expiration	7.4
Forestar Group [Member] | State [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	$ 1.0