Debt Obligations - Construction Loans (Details) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 30, 2018 USD ($) property	Jun. 30, 2018 USD ($) property
Debt Instrument [Line Items]
Property occupancy (as a percentage)	90.00%
Construction Loans
Debt Instrument [Line Items]
Number of construction projects to be financed \| property	2	2
Maximum loan amount	$ 77,691	$ 77,691
Amount outstanding	38,944	38,944
N Charleston, SC \| Construction Loans
Debt Instrument [Line Items]
Maximum loan amount	30,265	30,265
Amount outstanding	30,265	$ 30,265
Extension option		1 year
N Charleston, SC \| Construction Loans \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread on variable rate		1.70%
Nashville, TN \| Construction Loans
Debt Instrument [Line Items]
Maximum loan amount	47,426	$ 47,426
Amount outstanding	$ 8,679	$ 8,679
Nashville, TN \| Construction Loans \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread on variable rate		2.85%

This element represents the current and noncurrent portions of a long-term real estate loan with an initial maturity beyond one year or beyond the normal operating cycle, if longer, to finance building costs. The funds are disbursed as needed or in accordance with a prearranged plan; generally, a portion of the funds is disbursed at inception and the remainder as construction progresses. The money is repaid on completion of the project (generally one to seven years), usually from the proceeds of a mortgage loan. The rate is normally higher than the prime rate, and there is usually an origination fee. The effective yield on these loans tends to be high, and the lender has a security interest in the real property.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.16)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.16)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19,20,22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Name:	us-gaap_LongtermConstructionLoanCurrentAndNoncurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant