Land and Lot Option Purchase Contracts (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2012	Sep. 30, 2011
Land and lot option purchase contracts [Abstract]
Option Deposits	$ 18.1	$ 13.2

Total amount of earnest money deposits on land option contracts.

No definition available.

Name:	dhi_DepositsOnLandOptionContracts
Namespace Prefix:	dhi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant