Discontinued Operations (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Inventory impairments and abandonments	$ 637	$ 2,266	$ 0	$ 0	$ 0	$ 0	$ 147,611	$ 1,007	$ 2,903	$ 148,618	$ 6,499
Loss from discontinued operations, net of tax									(1,090)	(99)	(329)
Litigation settlement expense									1,300
Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total revenue									0	55	633
Home construction and land sales expenses (a)									1,245	61	612
Inventory impairments and abandonments									0	0	450
Gross loss									(1,245)	(6)	(429)
General and administrative expenses									173	125	101
Operating loss									(1,418)	(131)	(530)
Equity in (loss) income of unconsolidated entities									0	(1)	93
Other income (expense), net									19	5	(4)
Loss from discontinued operations before income taxes									(1,399)	(127)	(441)
Benefit from income taxes									(309)	(28)	(112)
Loss from discontinued operations, net of tax									$ (1,090)	$ (99)	$ (329)