Consolidated Statements of Operations (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2022	Mar. 31, 2021
Income Statement [Abstract]
Revenues	$ 7,999.0	$ 6,446.9	$ 15,052.4	$ 12,380.3
Cost of sales	5,429.9	4,650.9	10,335.6	8,983.5
Selling, general and administrative expense	695.1	621.5	1,361.0	1,207.4
Gain on sale of assets	0.0	0.0	0.0	(14.0)
Other (income) expense	(9.3)	(5.4)	(24.8)	(10.8)
Income before income taxes	1,883.3	1,179.9	3,380.6	2,214.2
Income tax expense	441.0	246.0	792.5	485.1
Net income	1,442.3	933.9	2,588.1	1,729.1
Net income attributable to noncontrolling interests	6.0	4.4	10.2	7.8
Net income attributable to D.R. Horton, Inc.	$ 1,436.3	$ 929.5	$ 2,577.9	$ 1,721.3
Basic net income per common share attributable to D.R. Horton, Inc. (in dollars per share)	$ 4.07	$ 2.57	$ 7.27	$ 4.74
Weighted average number of common shares	353.1	362.3	354.6	363.4
Diluted net income per common share attributable to D.R. Horton, Inc. (in dollars per share)	$ 4.03	$ 2.53	$ 7.20	$ 4.67
Adjusted weighted average number of common shares	356.3	367.2	358.2	368.6