Fair Value of Financial Instruments - Additional Information (Details) - Tremont Realty Capital LLC - USD ($) $ in Thousands	1 Months Ended	9 Months Ended
Aug. 31, 2016	Jun. 30, 2018	Sep. 30, 2017
Business Acquisition [Line Items]
Cash consideration	$ 2,466
Contingent consideration	$ 1,270	$ 5	$ 591
Duration of potential earn out	2 years
Gain on contingent consideration		$ 491

Business Combination, Contingent Consideration, Liability, Duration of Potential Earn-Out

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- Definition

Gain (Loss) On Business Combination, Contingent Consideration

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 35
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6911338&loc=d3e6819-128478

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 25
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6408-128476

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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

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