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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

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments.

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No definition available.

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Amount of increase (decrease) in deferred revenue.

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Carrying amount as of the balance sheet date of obligations due all related parties. For classified balance sheets, represents the current portion of such liabilities (due within one year or within the normal operating cycle if longer).

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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..

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

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Amount of deposits held by the entity for a related party (entity, shareholder, employee).

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Amount of transactions with related party during the financial reporting period.

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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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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.

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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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Related Party Transactions (Details)	3 Months Ended		9 Months Ended
Related Party Transactions (Details)	Jun. 30, 2019 USD ($) Lot	Jun. 30, 2018 USD ($)	Jun. 30, 2019 USD ($) Lot	Jun. 30, 2018 USD ($)	Oct. 01, 2018 USD ($)	Sep. 30, 2018 USD ($)
Related Party Transaction [Line Items]
Number of Units in Real Estate Property \| Lot	37,400		37,400
Due to Related Parties, Current	$ 700,000		$ 700,000			$ 3,300,000
Contract with Customer, Liability	9,900,000		9,900,000		$ 6,400,000	0
Contractual Obligation	9,900,000		9,900,000
Real estate	1,049,500,000		1,049,500,000			498,000,000
D.R. Horton, Inc. [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Selling, General and Administrative Expenses from Transactions with Related Party			1,600,000	$ 600,000
Deferred Revenue, Period Increase (Decrease)	2,000,000		3,600,000	3,200,000
Related Party Transaction, Purchases from Related Party	$ 600,000		1,400,000	100,000
General and Administrative Expense [Member] \| D.R. Horton, Inc. [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Expenses from Transactions with Related Party			$ 1,100,000	$ 600,000
D.R. Horton, Inc. [Member]
Related Party Transaction [Line Items]
Number of Lots Sold	995	141	1,903	324
Revenue from Related Parties	$ 75,200,000	$ 10,100,000	$ 145,400,000	$ 18,600,000
Under Contract [Member] \| D.R. Horton, Inc. [Member]
Related Party Transaction [Line Items]
Number of Units in Real Estate Property \| Lot	13,900		13,900
Related Party Deposit Liabilities	$ 83,700,000		$ 83,700,000			45,300,000
Right of First Offer [Member] \| D.R. Horton, Inc. [Member]
Related Party Transaction [Line Items]
Number of Units in Real Estate Property \| Lot	10,200		10,200
Land and Land Improvements [Member]
Related Party Transaction [Line Items]
Real estate	$ 988,700,000		$ 988,700,000			463,100,000
Land [Member]
Related Party Transaction [Line Items]
Real estate	60,800,000		60,800,000			$ 34,900,000
Other Expense [Member] \| D.R. Horton, Inc. [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Amounts of Transaction	4,700,000	4,600,000	8,400,000	12,800,000
Deposits [Member] \| D.R. Horton, Inc. [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Amounts of Transaction	$ 10,800,000	$ 2,900,000	$ 27,600,000	$ 16,900,000
Land [Member] \| D.R. Horton, Inc. [Member]
Related Party Transaction [Line Items]
Number of Lots Sold		79		79
Revenue from Related Parties		$ 2,000,000		$ 2,000,000
Land and Land Improvements [Member] \| D.R. Horton, Inc. [Member]
Related Party Transaction [Line Items]
Number of Units in Real Estate Property \| Lot	382		382
Minimum [Member] \| D.R. Horton, Inc. [Member]
Related Party Transaction [Line Items]
Investment Interest Rate			12.00%
Maximum [Member] \| D.R. Horton, Inc. [Member]
Related Party Transaction [Line Items]
Investment Interest Rate			16.00%