Segment Information (Details) $ in Thousands	3 Months Ended
Dec. 31, 2019 USD ($) segment state region	Dec. 31, 2018 USD ($)	Sep. 30, 2019 USD ($)
Segment Reporting [Abstract]
Number of states in which home building segments operate \| state	13
Number of regions in which entity operates \| region	3
Number of homebuilding segments \| segment	3
Segment Reporting Information [Line Items]
Revenue	$ 417,804	$ 402,040
Operating income	3,946	3,506
Depreciation and amortization	3,427	2,770
Capital expenditures	2,632	6,354
Assets	1,968,104		$ 1,957,644
Operating Segments
Segment Reporting Information [Line Items]
Operating income	38,808	31,036
Depreciation and amortization	2,902	2,426
Corporate and unallocated
Segment Reporting Information [Line Items]
Operating income	(34,862)	(27,530)
Depreciation and amortization	525	344
Capital expenditures	180	2,082
Assets	536,515		560,763
West Segment
Segment Reporting Information [Line Items]
Revenue	254,398	208,944
West Segment \| Operating Segments
Segment Reporting Information [Line Items]
Operating income	30,331	24,261
Depreciation and amortization	1,808	1,278
Capital expenditures	1,484	2,651
Assets	764,868		751,110
East Segment
Segment Reporting Information [Line Items]
Revenue	78,040	88,746
East Segment \| Operating Segments
Segment Reporting Information [Line Items]
Operating income	5,321	5,395
Depreciation and amortization	554	538
Capital expenditures	452	762
Assets	298,389		286,340
Southeast Segment
Segment Reporting Information [Line Items]
Revenue	85,366	104,350
Southeast Segment \| Operating Segments
Segment Reporting Information [Line Items]
Operating income	3,156	1,380
Depreciation and amortization	540	610
Capital expenditures	516	$ 859
Assets	$ 368,332		$ 359,431

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