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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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Related Party Transactions (Details)	3 Months Ended
Related Party Transactions (Details)	Dec. 31, 2019 USD ($) Lot	Dec. 31, 2018 USD ($)	Sep. 30, 2019 USD ($) Lot
Related Party Transaction [Line Items]
Number of Units in Real Estate Property \| Lot	44,500		38,300
Due to Related Parties, Current	$ 2,800,000		$ 2,200,000
Number of Lots Sold	2,422	518
Real estate	$ 1,066,800,000		1,028,900,000
Related Party Transaction, Purchase Obligation from Parent	918,600,000		$ 953,800,000
D.R. Horton, Inc. [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Selling, General and Administrative Expenses from Transactions with Related Party	1,300,000	$ 500,000
Deferred Revenue, Period Increase (Decrease)	(1,500,000)	(3,600,000)
Related Party Transaction, Purchases from Related Party	1,500,000	500,000
General and Administrative Expense [Member] \| D.R. Horton, Inc. [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Expenses from Transactions with Related Party	$ 600,000	$ 300,000
D.R. Horton, Inc. [Member]
Related Party Transaction [Line Items]
Number of Lots Sold	2,390	455
Revenue from Related Parties	$ 215,600,000	$ 32,600,000
Under Contract [Member] \| D.R. Horton, Inc. [Member]
Related Party Transaction [Line Items]
Number of Units in Real Estate Property \| Lot	12,700		12,800
Related Party Deposit Liabilities	$ 87,500,000		$ 88,700,000
Right of First Offer [Member] \| D.R. Horton, Inc. [Member]
Related Party Transaction [Line Items]
Number of Units in Real Estate Property \| Lot	12,900		10,600
Land [Member]
Related Party Transaction [Line Items]
Real estate	$ 15,400,000		$ 17,100,000
Other Expense [Member] \| D.R. Horton, Inc. [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Amounts of Transaction	5,200,000	3,000,000
Deposits [Member] \| D.R. Horton, Inc. [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Amounts of Transaction	$ 10,700,000	$ 12,100,000
Land [Member] \| D.R. Horton, Inc. [Member]
Related Party Transaction [Line Items]
Number of Lots Sold	36	0
Revenue from Related Parties	$ 7,200,000	$ 0
Minimum [Member] \| D.R. Horton, Inc. [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Rate	12.00%
Maximum [Member] \| D.R. Horton, Inc. [Member]
Related Party Transaction [Line Items]
Related Party Transaction, Rate	16.00%
Real Estate [Member] \| Residential Real Estate [Member]
Related Party Transaction [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	$ 217,100,000	$ 34,700,000