Discontinued Operations - Results of Discontinued Operations (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2018	Mar. 31, 2017
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Inventory impairments and lot option abandonments	$ 0	$ 282	$ 0	$ 282
Loss from discontinued operations, net of tax	(58)	(40)	(430)	(110)
Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total revenue	8	0	633	0
Home construction and land sales expenses	56	6	723	84
Inventory impairments and lot option abandonments	0	0	450	0
Gross loss	(48)	(6)	(540)	(84)
General and administrative expenses	31	60	47	91
Operating loss	(79)	(66)	(587)	(175)
Equity in income of unconsolidated entities	4	0	16	0
Other expense, net	(2)	(3)	(5)	(3)
Loss from discontinued operations before income taxes	(77)	(69)	(576)	(178)
Benefit from income taxes	(19)	(29)	(146)	(68)
Loss from discontinued operations, net of tax	$ (58)	$ (40)	$ (430)	$ (110)