Commitments and Contingencies Commitments and Contingencies (Details 1) - Homebuilding [Member] - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2015	Sep. 30, 2014
Rollforward of reserves for legal claims
Reserves for legal claims, beginning of period	$ 456.9	$ 482.0
Change in reserves	(44.0)	3.0
Payments	(49.9)	(22.1)
Reserves for legal claims, end of period	$ 451.0	$ 456.9

Amount of loss contingency liability.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

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- Definition

Amount of payments made reducing loss contingency liability.

+ References

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- Definition

Amount of increase (decrease) in loss contingency liability.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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