Inventory - Total Owned Inventory by Segment (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Sep. 30, 2017
Segment Reporting Information [Line Items]
Projects in progress	$ 1,579,716	$ 1,412,483
Land held for future development	87,718	112,565
Land held for sale	9,927	17,759
Total owned inventory	1,677,361	1,542,807
Corporate and unallocated
Segment Reporting Information [Line Items]
Projects in progress	204,237	187,385
Land held for future development	0	0
Land held for sale	24	1,100
Total owned inventory	204,261	188,485
West Segment \| Operating Segments
Segment Reporting Information [Line Items]
Projects in progress	751,745	673,828
Land held for future development	62,190	87,231
Land held for sale	1,484	3,848
Total owned inventory	815,419	764,907
East Segment \| Operating Segments
Segment Reporting Information [Line Items]
Projects in progress	285,068	250,002
Land held for future development	14,570	14,391
Land held for sale	7,522	11,578
Total owned inventory	307,160	275,971
Southeast Segment \| Operating Segments
Segment Reporting Information [Line Items]
Projects in progress	338,666	301,268
Land held for future development	10,958	10,943
Land held for sale	897	1,233
Total owned inventory	$ 350,521	$ 313,444

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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