Segment Information (Details) $ in Thousands	12 Months Ended
	Sep. 30, 2022 USD ($) segment state region	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	May 19, 2022
Segment Reporting [Abstract]
Number of states with active operations | state	13
Number of regions in which entity operates | region	3
Number of homebuilding segments | segment	3
Segment Reporting Information [Line Items]
Total revenue	$ 2,316,988	$ 2,140,303	$ 2,127,077
Total operating income	272,491	146,869	79,107
Depreciation and amortization	13,360	13,976	15,640
Capital expenditures	15,048	14,645	10,642
Assets	2,251,963	2,078,810
Imagine Homes
Segment Reporting [Abstract]
Equity method investment, ownership percentage				33.00%
Operating Segments
Segment Reporting Information [Line Items]
Total operating income	424,833	323,514	258,851
Depreciation and amortization	11,670	12,009	13,542
Corporate and unallocated
Segment Reporting Information [Line Items]
Total operating income	(152,342)	(176,645)	(179,744)
Depreciation and amortization	1,690	1,967	2,098
Capital expenditures	4,870	4,725	357
Assets	616,858	676,779
West
Segment Reporting Information [Line Items]
Total revenue	1,331,553	1,118,578	1,183,339
West | Operating Segments
Segment Reporting Information [Line Items]
Total operating income	253,961	181,303	161,786
Depreciation and amortization	8,178	7,250	8,227
Capital expenditures	7,755	6,924	5,063
Assets	995,339	819,317
East
Segment Reporting Information [Line Items]
Total revenue	560,747	569,835	477,624
East | Operating Segments
Segment Reporting Information [Line Items]
Total operating income	102,146	84,630	56,319
Depreciation and amortization	1,649	2,207	2,458
Capital expenditures	1,208	1,549	2,237
Assets	334,323	286,133
Southeast
Segment Reporting Information [Line Items]
Total revenue	424,688	451,890	466,114
Southeast | Operating Segments
Segment Reporting Information [Line Items]
Total operating income	68,726	57,581	40,746
Depreciation and amortization	1,843	2,552	2,857
Capital expenditures	1,215	1,447	$ 2,985
Assets	$ 305,443	$ 296,581