Inventory - Total Owned Inventory by Segment (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Sep. 30, 2018
Segment Reporting Information [Line Items]
Projects in progress	$ 1,631,946	$ 1,601,330
Land held for future development	83,177	83,173
Land held for sale	6,997	7,781
Total owned inventory	1,722,120	1,692,284
Corporate and unallocated
Segment Reporting Information [Line Items]
Projects in progress	211,772	198,990
Land held for future development	0	0
Land held for sale	0	24
Total owned inventory	211,772	199,014
West Segment \| Operating Segments
Segment Reporting Information [Line Items]
Projects in progress	785,702	763,453
Land held for future development	58,129	58,125
Land held for sale	0	0
Total owned inventory	843,831	821,578
East Segment \| Operating Segments
Segment Reporting Information [Line Items]
Projects in progress	277,300	280,761
Land held for future development	14,077	14,077
Land held for sale	3,906	4,580
Total owned inventory	295,283	299,418
Southeast Segment \| Operating Segments
Segment Reporting Information [Line Items]
Projects in progress	357,172	358,126
Land held for future development	10,971	10,971
Land held for sale	3,091	3,177
Total owned inventory	$ 371,234	$ 372,274

Carrying amount as of the balance sheet date of project in progress

No definition available.

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- Definition

Carrying amount as of the balance sheet date of parcels of land held for sale, and on which the entity has no intention or no further intention to perform construction activities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.6(a))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

The net carrying amount as of the balance sheet date of the sum of the various components of an operative builder's inventory, including finished homes. Operative builders primarily consist of entities that develop land, construct residential homes and commercial and industrial buildings thereon, and sell them to home buyers and operators of the commercial and industrial properties.

+ References

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- Definition

Carrying amount of land available for development.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.(a),1(d))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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