Inventory - Impairments and Lot Option Abandonment Charges, by Reportable Segment (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Real Estate, Write-down or Reserve [Line Items]
Land Held for Sale	$ 168	$ 470	$ 168	$ 564
Total impairment and abandonment charges	168	470	168	752
Total impairment and abandonment charges	168	470	618	752
Continuing Operations
Real Estate, Write-down or Reserve [Line Items]
Total impairment and abandonment charges	168	470	168	752
Discontinued Operations
Real Estate, Write-down or Reserve [Line Items]
Land Held for Sale	0	0	450	0
Total impairment and abandonment charges	0	0	450	0
West Segment
Real Estate, Write-down or Reserve [Line Items]
Land Held for Sale	0	0	0	94
East Segment
Real Estate, Write-down or Reserve [Line Items]
Land Held for Sale	168	470	168	470
Abandonments	$ 0	$ 0	$ 0	$ 188

Impairment Charges, Abandonment

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- Definition

Inventory Write Down and Impairment to Assets to be Disposed of

+ References

No definition available.

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- Definition

The aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=68055307&loc=d3e2611-110228

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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- Definition

Amount of loss from reductions in inventory due to subsequent measurement adjustments, including, but not limited to, physical deterioration, obsolescence, or changes in price levels.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 330
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=66092785&loc=d3e4542-108314

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 330
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-Section 35
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
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-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.2)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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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

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