Inventory - Total Owned Inventory by Segment (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Sep. 30, 2020
Segment Reporting Information [Line Items]
Projects in progress	$ 1,351,697	$ 1,309,585
Land held for future development	23,068	28,531
Land held for sale	8,851	12,622
Total owned inventory	1,383,616	1,350,738
Corporate and unallocated
Segment Reporting Information [Line Items]
Projects in progress	164,963	172,895
Land held for future development	0	0
Land held for sale	0	0
Total owned inventory	164,963	172,895
West Segment \| Operating Segments
Segment Reporting Information [Line Items]
Projects in progress	649,686	627,986
Land held for future development	3,483	3,483
Land held for sale	1,475	4,516
Total owned inventory	654,644	635,985
East Segment \| Operating Segments
Segment Reporting Information [Line Items]
Projects in progress	264,031	241,799
Land held for future development	14,077	14,077
Land held for sale	2,433	3,702
Total owned inventory	280,541	259,578
Southeast Segment \| Operating Segments
Segment Reporting Information [Line Items]
Projects in progress	273,017	266,905
Land held for future development	5,508	10,971
Land held for sale	4,943	4,404
Total owned inventory	$ 283,468	$ 282,280

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://fasb.org/us-gaap/role/ref/legacyRef
-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=120391452&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://fasb.org/us-gaap/role/ref/legacyRef
-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=120400017&loc=d3e572229-122910

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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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