Inventory - Narrative (Details) (USD $)	12 Months Ended
Sep. 30, 2012 Community home	Sep. 30, 2011 Community	Sep. 30, 2013 home
Real Estate Properties [Line Items]
Number of subtantially completed homes not subject to a sales contract	174		113
Total value of substantially completed homes	$ 39,700,000		$ 30,700,000
Owned inventory	1,099,132,000		1,304,694,000
Number of communities impaired	5	19
Deposits and non-refundable preacquisition costs incurred	24,923,000		37,313,000
Total remaining purchase price committed under all options	198,498,000		288,638,000
Minimum
Real Estate Properties [Line Items]
Discount rate	11.20%	12.60%
Maximum
Real Estate Properties [Line Items]
Discount rate	17.00%	18.20%
CALIFORNIA
Real Estate Properties [Line Items]
Owned inventory	$ 350,900,000		$ 388,100,000

Discounted Cash Flow Analyses, Number of Impaired Communities

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- Definition

Inventory Impairment Analysis, Discount Rate

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- Definition

Land Under Purchase Options, Consolidated and Unconsolidated VIEs, Total Remaining Obligations Under Option Agreements

+ References

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- Definition

Land Under Purchase Options, Deposits and Non-refundable Preacquisition Costs

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- Definition

Number of Real Estate Properties, Completed Unsold Homes

+ References

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- Definition

Value of Real Estate Properties, Complete Homes

+ References

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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

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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