Inventory - Total Owned Inventory by Segment (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Sep. 30, 2017
Segment Reporting Information [Line Items]
Projects in Progress	$ 1,601,330	$ 1,412,483
Land Held for Future Development	83,173	112,565
Land Held for Sale	7,781	17,759
Total owned inventory	1,692,284	1,542,807
Corporate and unallocated
Segment Reporting Information [Line Items]
Projects in Progress	198,990	187,385
Land Held for Future Development	0	0
Land Held for Sale	24	1,100
Total owned inventory	199,014	188,485
West Segment
Segment Reporting Information [Line Items]
Projects in Progress	763,453	673,828
Land Held for Future Development	58,125	87,231
Land Held for Sale	0	3,848
Total owned inventory	821,578	764,907
East Segment
Segment Reporting Information [Line Items]
Projects in Progress	280,761	250,002
Land Held for Future Development	14,077	14,391
Land Held for Sale	4,580	11,578
Total owned inventory	299,418	275,971
Southeast Segment
Segment Reporting Information [Line Items]
Projects in Progress	358,126	301,268
Land Held for Future Development	10,971	10,943
Land Held for Sale	3,177	1,233
Total owned inventory	$ 372,274	$ 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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