Basis of Presentation and Summary of Significant Accounting Policies - Revenue Recognition (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Sep. 30, 2022
Disaggregation of Revenue [Line Items]
Total revenue	$ 572,544	$ 526,666	$ 1,561,380	$ 1,489,321
Customer deposits	32,852		32,852		$ 34,270
Contract with customer, liability, revenue recognized	6,200		28,400
Homebuilding revenue
Disaggregation of Revenue [Line Items]
Total revenue	570,535	523,229	1,556,626	1,477,166
Land sales and other revenue
Disaggregation of Revenue [Line Items]
Total revenue	$ 2,009	$ 3,437	$ 4,754	$ 12,155