Basis of Presentation and Summary of Significant Accounting Policies (Details) $ in Thousands	6 Months Ended	12 Months Ended
	Mar. 31, 2023 USD ($)	Sep. 30, 2023 USD ($) home	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)
Summary of Significant Accounting Policies [Line Items]
Threshold number of homes below a minimum threshold of profitability | home		10
Measurement threshold of likelihood of being realized (percent)		50.00%
Tax refunds received	$ 9,200	$ 9,987	$ 0	$ 1,078
Additional interest payment	$ 400
Customer deposits		27,577	34,270
Contract with customer, liability, revenue recognized		29,200
Refunded by buyer		4,600
Advertising costs		$ 15,100	$ 14,400	$ 14,000
Minimum
Summary of Significant Accounting Policies [Line Items]
Estimated time to develop, sell, construct and close all homes (in years)		3 years
Estimated future warranty costs as a percentage or revenue (percent)		0.30%
Maximum
Summary of Significant Accounting Policies [Line Items]
Estimated time to develop, sell, construct and close all homes (in years)		5 years
Estimated future warranty costs as a percentage or revenue (percent)		1.00%