Segment Information (Details) $ in Thousands	3 Months Ended
Dec. 31, 2018 USD ($) segment state region	Dec. 31, 2017 USD ($)	Sep. 30, 2018 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	$ 402,040	$ 372,489
Operating income	3,506	6,681
Depreciation and amortization	2,770	2,507
Capital Expenditures	6,354	3,702
Assets	2,103,390		$ 2,128,102
Operating Segments
Segment Reporting Information [Line Items]
Operating income	31,036	35,416
Depreciation and amortization	2,426	2,274
Corporate and unallocated
Segment Reporting Information [Line Items]
Operating income	(27,530)	(28,735)
Depreciation and amortization	344	233
Capital Expenditures	2,082	588
Assets	551,401		542,713
West Segment
Segment Reporting Information [Line Items]
Revenue	208,944	177,971
West Segment \| Operating Segments
Segment Reporting Information [Line Items]
Operating income	24,261	21,110
Depreciation and amortization	1,278	1,256
Capital Expenditures	2,651	1,776
Assets	855,823		835,230
East Segment
Segment Reporting Information [Line Items]
Revenue	88,746	88,853
East Segment \| Operating Segments
Segment Reporting Information [Line Items]
Operating income	5,395	7,396
Depreciation and amortization	538	439
Capital Expenditures	762	595
Assets	305,232		335,474
Southeast Segment
Segment Reporting Information [Line Items]
Revenue	104,350	105,665
Southeast Segment \| Operating Segments
Segment Reporting Information [Line Items]
Operating income	1,380	6,910
Depreciation and amortization	610	579
Capital Expenditures	859	$ 743
Assets	$ 390,934		$ 414,685

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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