Supplemental Guarantor Information (Details 2) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
OPERATING ACTIVITIES
Net cash used in operating activities	$ (840.3)	$ (79.4)
INVESTING ACTIVITIES
Purchases of property and equipment	(25.3)	(5.5)
Purchases of marketable securities	(28.9)	(162.8)
Proceeds from the sale or maturity of marketable securities	325.4	157.5
Decrease (increase) in restricted cash	(5.2)	8.4
Net principal increase of mortgage loans held in portfolio and real estate owned	0	(3.2)
Payments to Acquire Other Investments	(18.6)	0
Payment related to acquisition of a business	(9.4)	0
Net cash (used in) provided by investing activities	238.0	(5.6)
FINANCING ACTIVITIES
Net change in notes payable	747.6	34.4
Proceeds from stock associated with certain employee benefit plans	17.7	21.6
Cash dividends paid	(60.2)	(23.8)
Net cash provided by (used in) financing activities	705.1	32.2
(Decrease) increase in cash and cash equivalents	102.8	(52.8)
Cash and cash equivalents at beginning of period	1,047.7	732.6
Cash and cash equivalents at end of period	1,150.5	679.8
D.R. Horton, Inc. [Member]
OPERATING ACTIVITIES
Net cash used in operating activities	(310.0)	(17.3)
INVESTING ACTIVITIES
Purchases of property and equipment	(12.9)	(1.6)
Purchases of marketable securities	(28.9)	(162.8)
Proceeds from the sale or maturity of marketable securities	325.4	157.5
Decrease (increase) in restricted cash	(4.7)	8.6
Payments to Acquire Other Investments	(18.6)
Payment related to acquisition of a business	(9.4)
Net cash (used in) provided by investing activities	250.9	1.7
FINANCING ACTIVITIES
Net change in notes payable	689.6	(11.6)
Net change in intercompany receivables/payables	(495.3)	(26.8)
Proceeds from stock associated with certain employee benefit plans	17.7	21.6
Cash dividends paid	(60.2)	(23.8)
Net cash provided by (used in) financing activities	151.8	(40.6)
(Decrease) increase in cash and cash equivalents	92.7	(56.2)
Cash and cash equivalents at beginning of period	968.9	681.3
Cash and cash equivalents at end of period	1,061.6	625.1
Guarantor Subsidiaries [Member]
OPERATING ACTIVITIES
Net cash used in operating activities	(484.2)	(63.2)
INVESTING ACTIVITIES
Purchases of property and equipment	(4.8)	(3.5)
Decrease (increase) in restricted cash	(0.5)	(0.1)
Net cash (used in) provided by investing activities	(5.3)	(3.6)
FINANCING ACTIVITIES
Net change in notes payable	0	(1.3)
Net change in intercompany receivables/payables	497.5	70.0
Net cash provided by (used in) financing activities	497.5	68.7
(Decrease) increase in cash and cash equivalents	8.0	1.9
Cash and cash equivalents at beginning of period	56.3	31.3
Cash and cash equivalents at end of period	64.3	33.2
Non-Guarantor Subsidiaries [Member]
OPERATING ACTIVITIES
Net cash used in operating activities	(16.1)	1.1
INVESTING ACTIVITIES
Purchases of property and equipment	(7.6)	(0.4)
Decrease (increase) in restricted cash	0	(0.1)
Net principal increase of mortgage loans held in portfolio and real estate owned		3.2
Net cash (used in) provided by investing activities	(7.6)	(3.7)
FINANCING ACTIVITIES
Net change in notes payable	58.0	47.3
Net change in intercompany receivables/payables	(2.2)	(43.2)
Cash dividends paid	(30.0)
Net cash provided by (used in) financing activities	25.8	4.1
(Decrease) increase in cash and cash equivalents	2.1	1.5
Cash and cash equivalents at beginning of period	22.5	20.0
Cash and cash equivalents at end of period	24.6	21.5
Eliminations [Member]
OPERATING ACTIVITIES
Net cash used in operating activities	(30.0)
FINANCING ACTIVITIES
Cash dividends paid	30.0
Net cash provided by (used in) financing activities	$ 30.0