Fair Value Measurements - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016
Fair Value Disclosures [Abstract]
Impairment of projects in process	$ 1,000	$ 1,700	$ 13,700
Impairment of land held for sale	5,900	600	800
Impairment of unconsolidated entity investment	$ (341)	$ 0	$ 0

Equity Method Investments, Impairment Of Unconsolidated Entity Investments, Continuing Operations

No definition available.

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- References

No definition available.

+ Details

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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
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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- Definition

Amount recognized as an operating expense or loss during the period to reduce the carrying amount of a project that has been impaired but not abandoned.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=68055307&loc=d3e2420-110228

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

+ Details

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