Inventory - Total Owned Inventory by Segment (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Sep. 30, 2016
Segment Reporting Information [Line Items]
Projects in Progress	$ 1,452,763	$ 1,326,577
Land held for future development	152,724	213,006
Land held for sale	25,585	29,696
Total owned inventory	1,631,072	1,569,279
Corporate and unallocated
Segment Reporting Information [Line Items]
Projects in Progress	199,195	186,987
Land held for future development	0	0
Land held for sale	1,102	1,099
Total owned inventory	200,297	188,086
West Segment \| Operating Segments
Segment Reporting Information [Line Items]
Projects in Progress	647,239	586,420
Land held for future development	128,132	172,015
Land held for sale	8,144	6,577
Total owned inventory	783,515	765,012
East Segment \| Operating Segments
Segment Reporting Information [Line Items]
Projects in Progress	297,967	276,785
Land held for future development	13,649	30,036
Land held for sale	15,129	20,930
Total owned inventory	326,745	327,751
Southeast Segment \| Operating Segments
Segment Reporting Information [Line Items]
Projects in Progress	308,362	276,385
Land held for future development	10,943	10,955
Land held for sale	1,210	1,090
Total owned inventory	$ 320,515	$ 288,430

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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