Segment Information (Details) $ in Thousands	3 Months Ended	6 Months Ended
Mar. 31, 2017 USD ($) segment state	Mar. 31, 2016 USD ($)	Mar. 31, 2017 USD ($) segment state region	Mar. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)
Segment Reporting [Abstract]
Number of states in which home building segments operate \| state	13		13
Number of regions in which entity operates \| segment	3		3
Number of homebuilding segments \| region			3
Segment Reporting Information [Line Items]
Revenue	$ 425,468	$ 385,607	$ 764,709	$ 730,056
Operating income	7,511	3,030	8,786	12,178
Depreciation and amortization	3,155	3,056	5,832	6,047
Write-off of deposit on legacy land investment			2,700	0
Excess insurance recovery		3,600		3,600
Capital Expenditures			5,677	6,017
Total capital expenditures			5,677	6,017
Assets	2,175,201		2,175,201		$ 2,213,158
Operating Segments
Segment Reporting Information [Line Items]
Operating income	43,885	34,998	71,472	66,588
Depreciation and amortization	2,799	2,513	5,042	4,977
Corporate and unallocated
Segment Reporting Information [Line Items]
Operating income	(36,374)	(31,968)	(62,686)	(54,410)
Depreciation and amortization	356	543	790	1,070
Capital Expenditures			191	216
Assets	689,686		689,686		756,238
West Segment
Segment Reporting Information [Line Items]
Revenue	185,155	179,930	356,904	337,126
West Segment \| Operating Segments
Segment Reporting Information [Line Items]
Operating income	20,779	18,927	41,794	35,713
Depreciation and amortization	1,545	1,332	2,793	2,550
Capital Expenditures			3,165	2,906
Assets	807,218		807,218		778,521
East Segment
Segment Reporting Information [Line Items]
Revenue	116,640	106,835	200,799	207,392
East Segment \| Operating Segments
Segment Reporting Information [Line Items]
Operating income	10,532	8,333	12,089	12,480
Depreciation and amortization	598	634	1,127	1,431
Capital Expenditures			1,446	1,273
Assets	335,172		335,172		344,898
Southeast Segment
Segment Reporting Information [Line Items]
Revenue	123,673	98,842	207,006	185,538
Southeast Segment \| Operating Segments
Segment Reporting Information [Line Items]
Operating income	12,574	7,738	17,589	18,395
Depreciation and amortization	656	$ 547	1,122	996
Capital Expenditures			875	$ 1,622
Assets	$ 343,125		$ 343,125		$ 333,501

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Number of Regions in which Entity Operates

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Total Capital Expenditure, cash and non-cash

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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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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