Variable Interest Entities (Details) - USD ($) $ in Thousands		Mar. 31, 2018	Sep. 30, 2017	Mar. 31, 2017	Sep. 30, 2016
Variable Interest Entity [Line Items]
Real estate properties, net		$ 993,250	$ 902,281
Cash and cash equivalents		30,974	12,383	$ 43,147	$ 27,399
Deposits and escrows		23,655	27,839
Other assets		7,005	9,359
Real estate property held for sale		0	8,969
Total Assets	[1]	1,088,631	993,897
Mortgages payable, net of deferred costs of $6,550 and $6,345		743,225	697,826
Accounts payable and accrued liabilities		17,002	22,348
Total Liabilities	[1]	797,255	757,192
Real estate properties, net of accumulated depreciation		67,643	64,290
Deferred mortgage costs		6,922	6,727
Variable interest entity
Variable Interest Entity [Line Items]
Real estate properties, net		625,714	707,546
Cash and cash equivalents		9,228	8,626
Deposits and escrows		8,632	13,873
Other assets		5,765	8,148
Real estate property held for sale		0	8,969
Total Assets		649,339	747,162
Mortgages payable, net of deferred costs of $6,550 and $6,345		479,093	558,568
Accounts payable and accrued liabilities		7,550	14,419
Total Liabilities		486,643	572,987
Real estate properties, net of accumulated depreciation		48,037	52,873
Mortgages
Variable Interest Entity [Line Items]
Deferred mortgage costs		6,550	6,345
Mortgages | Variable interest entity
Variable Interest Entity [Line Items]
Deferred mortgage costs		$ 4,189	$ 5,170

[1] The Company's consolidated balance sheets include the assets and liabilities of consolidated variable interest entities (VIEs). See note 6. The consolidated balance sheets include the following amounts related to the Company's VIEs as of March 31, 2018 and September 30, 2017, respectively: $625,714 and $707,546 of real estate properties, $9,228 and $8,626 of cash and cash equivalents, $8,632 and $13,873 of deposits and escrows, $5,765 and $8,148 of other assets, $0 and $8,969 of real estate properties held for sale, $479,093 and $558,568 of mortgages payable and $7,550 and $14,419 of accounts payable and accrued liabilities.