Consolidated Statements of Operations (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Income Statement [Abstract]
Revenues	$ 3,519.0	$ 3,332.7
Cost of sales	2,751.1	2,580.1
Selling, general and administrative expense	402.8	384.2
Gain on sale of assets	(2.0)	(13.4)
Other (income) expense	(8.6)	(9.4)
Income before income taxes	375.7	391.2
Income tax expense	89.0	202.4
Net income	286.7	188.8
Net loss attributable to noncontrolling interests	(0.5)	(0.5)
Net income attributable to D.R. Horton, Inc.	$ 287.2	$ 189.3
Basic net income per common share attributable to D.R. Horton, Inc. (in dollars per share)	$ 0.77	$ 0.50
Weighted average number of common shares	375.1	375.8
Diluted net income per common share attributable to D.R. Horton, Inc. (in dollars per share)	$ 0.76	$ 0.49
Adjusted weighted average number of common shares	380.1	383.8