Homebuilding revenues expressed as a percentage of consolidated revenues.

No definition available.

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- Definition

The number of markets the entity operates in as of the balance sheet date.

+ References

No definition available.

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- Definition

Number of Projects

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No definition available.

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- Definition

The difference between the carrying value and the sale price of real estate or properties that were intended to be sold or held for capital appreciation or rental income. This element refers to the gain (loss) included in earnings and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

+ References

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

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- Definition

The number of states the entity operates in as of the balance sheet date.

+ References

No definition available.

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- Definition

The cash inflow from sale of buildings.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
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- Definition

Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

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

No definition available.

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Segment Information - Narrative (Details) $ in Millions	3 Months Ended			12 Months Ended
Segment Information - Narrative (Details) $ in Millions	Sep. 30, 2019 USD ($) Projects State OperatingDivisions Market Segments	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Sep. 30, 2019 USD ($) Projects State Market	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)
Segment Reporting Information [Line Items]
Proceeds from Sale of Buildings				$ 143.8	$ 292.9	$ 0.0
Gain (Loss) on Sale of Properties				53.9	18.8	$ 0.0
Property and Equipment, Gross	$ 723.1			$ 723.1	$ 645.8
Home Building [Member]
Segment Reporting Information [Line Items]
Number of homebuilding operating divisions \| OperatingDivisions	52
Number of homebuilding reporting segments \| Segments	6
Homebuilding percentage of consolidated revenues				97.00%	97.00%	98.00%
Number of housing construction markets \| Market	90			90
Number of housing construction states \| State	29			29
Gain (Loss) on Sale of Properties				$ 2.0	$ 15.8
Other Segments [Member]
Segment Reporting Information [Line Items]
Gain (Loss) on Sale of Properties				51.9	0.0
Other Segments [Member] \| Multifamily [Member]
Segment Reporting Information [Line Items]
Property and Equipment, Gross	$ 153.9			$ 153.9	$ 171.4
Forestar Group [Member]
Segment Reporting Information [Line Items]
Number of housing construction markets \| Market	51			51
Number of housing construction states \| State	20			20
Asset under Construction [Member] \| Other Segments [Member] \| Multifamily [Member]
Segment Reporting Information [Line Items]
Number of Projects \| Projects	4			4
Assets Leased to Others [Member] \| Other Segments [Member] \| Multifamily [Member]
Segment Reporting Information [Line Items]
Number of Projects \| Projects	2			2
Asset Under Contract to Sell [Member] \| Other Segments [Member] \| Multifamily [Member]
Segment Reporting Information [Line Items]
Number of Projects \| Projects	1			1
DHIC1 [Member] \| Other Segments [Member] \| Multifamily [Member]
Segment Reporting Information [Line Items]
Proceeds from Sale of Buildings			$ 73.4
Gain (Loss) on Sale of Properties			$ 29.3
DHIC2 [Member] \| Other Segments [Member] \| Multifamily [Member]
Segment Reporting Information [Line Items]
Proceeds from Sale of Buildings		$ 60.0
Gain (Loss) on Sale of Properties		$ 22.6