Real Estate - Real Estate (Details)	6 Months Ended
Jun. 30, 2018 USD ($) Lot Project	Dec. 31, 2017 USD ($)
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]
Real estate \| $	$ 360,875,000	$ 130,380,000
Number of Projects \| Project	24
Payments to Acquire Real Estate \| $	$ 213,686,000
Number of Units in Real Estate Property \| Lot	19,100
D.R. Horton, Inc. [Member]
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]
Notes Receivable, Related Parties	12.00%
Entitled, developed and under development projects
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]
Real estate \| $	$ 357,882,000	127,442,000
Entitled, developed and under development projects \| D.R. Horton, Inc. [Member]
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]
Real estate \| $	$ 34,916,000
Residential Real Estate [Member]
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]
Number of Lots Acquired \| Lot	9,300
Right of First Offer [Member] \| D.R. Horton, Inc. [Member]
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]
Number of Units in Real Estate Property \| Lot	6,700
Under Contract [Member] \| D.R. Horton, Inc. [Member]
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]
Number of Units in Real Estate Property \| Lot	4,400
Under Contract [Member] \| Unaffiliated Customer [Member]
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]
Number of Units in Real Estate Property \| Lot	360
Land [Member]
SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items]
Real estate \| $	$ 2,993,000	$ 2,938,000

Number of Lots Acquired

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- Definition

The interest rate for investments that have an interest rate. For fixed rate investments, this indicates the fixed interest rate. If the investment has a variable interest rate, the rate stated here may be the rate that is currently relevant. In this case the "Investment, Interest Rate is Current Rate for Variable Rate Investment Flag", "Investment, Interest Rate is Discount Rate at Purchase Flag", "Investment, Interest Rate Reflects Current Yield Flag" should be used. If one of these flags are not appropriate to explain the interest rate that is indicated, then a new flag should be added or an explanation should be included in "Investment, Additional Information".

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 12
-Sentence Column A

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- Definition

Carrying amount as of the balance sheet date, net of valuation allowances and impairment losses, of costs of land expected to be developed in the near term plus capitalized costs of development, for purposes of selling completed units to home buyers or commercial or industrial entities..

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.6(a))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

The number of real estate properties owned as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

The number of units in a real estate property owned as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

The cash outflow from the acquisition of a piece of land, anything permanently fixed to it, including buildings, structures on it and so forth; includes real estate intended to generate income for the owner; excludes real estate acquired for use by the owner.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3213-108585

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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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