Typical time period from loan origination to commitment of the loan to a third-party purchaser.

No definition available.

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- Definition

Mortgage loans held for sale not committed to third-party purchasers.

+ References

No definition available.

+ Details

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Period Type:	instant

- Details

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- Definition

This represents the number of major financial institutions to which an entity sold loans pursuant to a repurchase agreement.

+ References

No definition available.

+ Details

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- Definition

The percentage of mortgage loans sold to major purchasers during the period.

+ References

No definition available.

+ Details

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Namespace Prefix:	dhi_
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- Details

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- Definition

The net gain (loss) resulting from a sale of loans, including adjustments to record loans classified as held-for-sale at the lower-of-cost-or-market and fair value adjustments to loan held for investment purposes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.13(h))

-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-04.3(a))

-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Carrying amount of mortgage loans to individuals not classified as held for investment but are held-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 948

-SubTopic 310

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6490309&loc=d3e48678-111004

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7(a)(3))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher OTS

-Name Federal Regulation (FR)

-Number Title 12

-Chapter V

-Section 563c.102

-Subsection I

-Paragraph 8

-Subparagraph h

-LegacyDoc This is a non-GAAP reference that was included in the 2009 taxonomy. It will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Permanent Investor

-URI http://asc.fasb.org/extlink&oid=6520390

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 65

-Paragraph 1, 34

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6375948&loc=d3e4428-111522

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- Definition

The carrying amount of the outstanding balance due under the mortgage loan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 948

-SubTopic 310

-Section S99

-Paragraph 1

-Subparagraph (SX 210.12-29)

-URI http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph c

-Subparagraph Schedule IV

-Article 5

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 29

-Article 12

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 10

-Section S99

-Paragraph 6

-Subparagraph (SX 210.5-04.(c) Schedule IV)

-URI http://asc.fasb.org/extlink&oid=6882300&loc=d3e5864-122674

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- Definition

Aggregate notional amount of all derivatives designated as a fair value hedging instrument. The notional amount relates to a number of currency units, shares, bushels, pounds, or other units specified in a derivative instrument.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Notional Amount

-URI http://asc.fasb.org/extlink&oid=6519104

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- Definition

Aggregate notional amount of all interest rate derivatives not designated as hedging instruments. Notional amount refers to the monetary amount specified in the interest rate derivative contract.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1B

-URI http://asc.fasb.org/extlink&oid=6935481&loc=SL5580258-113959

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Notional Amount

-URI http://asc.fasb.org/extlink&oid=6519104

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1A

-Subparagraph (d)

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Mortgage Loans (Details Textual) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Mar. 31, 2013 Institution	Mar. 31, 2012	Mar. 31, 2013	Mar. 31, 2012	Sep. 30, 2012
Derivative [Line Items]
Commitment Of Hedged Loans To Third Party Purchasers	3 days
Financial Services [Member]
Mortgage Loans [Abstract]
Mortgage loans held for sale	$ 394.3		$ 394.3		$ 345.3
Aggregate outstanding principal balance of mortgage loans held for sale	382.9		382.9		332.9
Net gain on sales of loans	26.7	14.9	54.2	25.1
Percentage of mortgage loans sold to major purchasers	56.00%
Number of Major Financial Institutions	1
Mortgage loans held for sale not committed to third-party purchasers	223.5		223.5
Notional amounts of hedging instruments, Total	224.0		224.0
Financial Services [Member] \| Interest rate lock commitments [Member]
Mortgage Loans [Abstract]
Notional amount of interest rate derivatives	332.2		332.2
Financial Services [Member] \| Best-efforts and mandatory commitments [Member]
Mortgage Loans [Abstract]
Notional amount of interest rate derivatives	15.7		15.7
Financial Services [Member] \| Hedging Instruments related to IRLCs [Member]
Mortgage Loans [Abstract]
Notional amount of interest rate derivatives	$ 283.0		$ 283.0