Inventory - Total Owned Inventory by Segment (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Sep. 30, 2019
Segment Reporting Information [Line Items]
Projects in progress	$ 1,556,053	$ 1,463,055
Land held for future development	28,531	28,531
Land held for sale	10,716	12,662
Total owned inventory	1,595,300	1,504,248
Corporate and unallocated
Segment Reporting Information [Line Items]
Projects in progress	195,913	192,287
Land held for future development	0	0
Land held for sale	0	0
Total owned inventory	195,913	192,287
West Segment \| Operating Segments
Segment Reporting Information [Line Items]
Projects in progress	747,692	723,094
Land held for future development	3,483	3,483
Land held for sale	4,153	5,160
Total owned inventory	755,328	731,737
East Segment \| Operating Segments
Segment Reporting Information [Line Items]
Projects in progress	279,900	228,937
Land held for future development	14,077	14,077
Land held for sale	3,166	4,104
Total owned inventory	297,143	247,118
Southeast Segment \| Operating Segments
Segment Reporting Information [Line Items]
Projects in progress	332,548	318,737
Land held for future development	10,971	10,971
Land held for sale	3,397	3,398
Total owned inventory	$ 346,916	$ 333,106

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

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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=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://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=119400593&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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