Inventory - Summary of Interests in Lot Option Agreements (Details) - Unconsolidated lot option agreements - USD ($) $ in Thousands	Mar. 31, 2020	Sep. 30, 2019
Real Estate Properties [Line Items]
Deposits & Non-refundable Pre-acquisition Costs Incurred	$ 67,557	$ 78,202
Remaining Obligation	$ 382,412	$ 389,705

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.

No definition available.

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