Interest - Schedule of Capitalized Interest (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Real Estate Inventory, Capitalized Interest Costs [Roll Forward]
Capitalized interest in inventory, beginning of period	$ 144,756	$ 149,034	$ 144,645	$ 139,203
Interest incurred	26,782	25,803	77,506	76,850
Capitalized interest impaired	0	0	(13,907)	0
Interest expense not qualified for capitalization and included as other expense	(961)	(205)	(1,800)	(5,290)
Capitalized interest amortized to home construction and land sales expenses	(21,752)	(22,450)	(57,619)	(58,581)
Capitalized interest in inventory, end of period	$ 148,825	$ 152,182	$ 148,825	$ 152,182