Commitments and Contingencies Commitments and Contingencies (Details 1) (Homebuilding [Member], USD $) In Millions, unless otherwise specified	6 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Homebuilding [Member]
Rollforward of reserves for legal claims
Reserves for legal claims, beginning of period	$ 456.9	$ 482.0
Payments	(28.3)	(10.4)
Increase (decrease) in reserve	20.8	(17.4)
Reserves for legal claims, end of period	$ 449.4	$ 454.2

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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Amount of payments made reducing loss contingency liability.

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Amount of increase (decrease) in loss contingency liability.

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