Supplemental Guarantor Information (Details 1) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Financial Services [Abstract]
Income before income taxes	[1]	$ 378.6	$ 333.8	$ 920.4	$ 784.6
Income tax expense		128.8	112.4	317.8	272.8
Net income		249.8	221.4	602.6	511.8
Comprehensive income		249.8	221.4	601.2	511.8
Homebuilding [Member]
Homebuilding:
Revenues		3,148.8	2,876.4	8,210.8	7,468.0
Cost of sales		2,523.0	2,320.4	6,584.3	6,026.9
Total gross profit		625.8	556.0	1,626.5	1,441.1
Selling, general and administrative expense		280.4	257.8	782.0	738.2
Equity in (income) of subsidiaries		0.0	0.0	0.0	0.0
Other (income)		(3.8)	(3.9)	(16.8)	(13.9)
Financial Services [Abstract]
Income before income taxes		349.2	302.1	861.3	716.8
Financial Services [Member]
Financial Services [Abstract]
Revenues		83.1	74.4	205.4	183.6
General and administrative expense		56.4	46.0	153.5	124.6
Interest and other (income)		(2.7)	(3.3)	(7.2)	(8.8)
Income before income taxes		29.4	31.7	59.1	67.8
D.R. Horton, Inc. [Member]
Financial Services [Abstract]
Income before income taxes		381.3	333.8	925.6	784.6
Income tax expense		130.6	112.4	319.6	272.8
Net income		250.7	221.4	606.0	511.8
Comprehensive income		250.7	221.4	604.6	511.8
D.R. Horton, Inc. [Member] | Homebuilding [Member]
Homebuilding:
Revenues		1,040.8	890.5	2,700.7	2,314.4
Cost of sales		836.9	718.0	2,170.5	1,865.6
Total gross profit		203.9	172.5	530.2	448.8
Selling, general and administrative expense		126.6	116.2	357.4	338.9
Equity in (income) of subsidiaries		(303.3)	(277.1)	(745.9)	(673.4)
Other (income)		(0.7)	(0.4)	(6.9)	(1.3)
Financial Services [Abstract]
Income before income taxes		381.3	333.8	925.6	784.6
D.R. Horton, Inc. [Member] | Financial Services [Member]
Financial Services [Abstract]
Revenues		0.0	0.0	0.0	0.0
General and administrative expense		0.0	0.0	0.0	0.0
Interest and other (income)		0.0	0.0	0.0	0.0
Income before income taxes		0.0	0.0	0.0	0.0
Guarantor Subsidiaries [Member]
Financial Services [Abstract]
Income before income taxes		274.5	250.0	681.8	619.7
Income tax expense		92.4	83.0	234.0	213.9
Net income		182.1	167.0	447.8	405.8
Comprehensive income		182.1	167.0	447.8	405.8
Guarantor Subsidiaries [Member] | Homebuilding [Member]
Homebuilding:
Revenues		2,118.6	1,985.9	5,526.1	5,153.6
Cost of sales		1,693.2	1,601.0	4,429.3	4,156.0
Total gross profit		425.4	384.9	1,096.8	997.6
Selling, general and administrative expense		151.5	135.5	418.4	381.0
Equity in (income) of subsidiaries		0.0	0.0	0.0	0.0
Other (income)		(0.6)	(0.6)	(3.4)	(3.1)
Financial Services [Abstract]
Income before income taxes		274.5	250.0	681.8	619.7
Guarantor Subsidiaries [Member] | Financial Services [Member]
Financial Services [Abstract]
Revenues		0.0	0.0	0.0	0.0
General and administrative expense		0.0	0.0	0.0	0.0
Interest and other (income)		0.0	0.0	0.0	0.0
Income before income taxes		0.0	0.0	0.0	0.0
Non-Guarantor Subsidiaries [Member]
Financial Services [Abstract]
Income before income taxes		28.8	27.1	64.1	53.7
Income tax expense		10.8	10.3	23.9	20.6
Net income		18.0	16.8	40.2	33.1
Comprehensive income		18.0	16.8	40.2	33.1
Non-Guarantor Subsidiaries [Member] | Homebuilding [Member]
Homebuilding:
Revenues		0.0	0.0	0.0	0.0
Cost of sales		0.8	1.4	(4.7)	5.3
Total gross profit		(0.8)	(1.4)	4.7	(5.3)
Selling, general and administrative expense		2.3	6.1	6.2	18.3
Equity in (income) of subsidiaries		0.0	0.0	0.0	0.0
Other (income)		(2.5)	(2.9)	(6.5)	(9.5)
Financial Services [Abstract]
Income before income taxes		(0.6)	(4.6)	5.0	(14.1)
Non-Guarantor Subsidiaries [Member] | Financial Services [Member]
Financial Services [Abstract]
Revenues		83.1	74.4	205.4	183.6
General and administrative expense		56.4	46.0	153.5	124.6
Interest and other (income)		(2.7)	(3.3)	(7.2)	(8.8)
Income before income taxes		29.4	31.7	59.1	67.8
Eliminations [Member]
Financial Services [Abstract]
Income before income taxes		(306.0)	(277.1)	(751.1)	(673.4)
Income tax expense		(105.0)	(93.3)	(259.7)	(234.5)
Net income		(201.0)	(183.8)	(491.4)	(438.9)
Comprehensive income		(201.0)	(183.8)	(491.4)	(438.9)
Eliminations [Member] | Homebuilding [Member]
Homebuilding:
Revenues		(10.6)	0.0	(16.0)	0.0
Cost of sales		(7.9)	0.0	(10.8)	0.0
Total gross profit		(2.7)	0.0	(5.2)	0.0
Selling, general and administrative expense		0.0	0.0	0.0	0.0
Equity in (income) of subsidiaries		303.3	277.1	745.9	673.4
Other (income)		0.0	0.0	0.0	0.0
Financial Services [Abstract]
Income before income taxes		(306.0)	(277.1)	(751.1)	(673.4)
Eliminations [Member] | Financial Services [Member]
Financial Services [Abstract]
Revenues		0.0	0.0	0.0	0.0
General and administrative expense		0.0	0.0	0.0	0.0
Interest and other (income)		0.0	0.0	0.0	0.0
Income before income taxes		$ 0.0	$ 0.0	$ 0.0	$ 0.0

[1] Expenses maintained at the corporate level consist primarily of interest and property taxes, which are capitalized and amortized to cost of sales or expensed directly, and the expenses related to operating the Company’s corporate office. The amortization of capitalized interest and property taxes is allocated to each segment based on the segment’s cost of sales, while those expenses associated with the corporate office are allocated to each segment based on the segment’s inventory balances.