Real Estate Properties - Purchase Price Allocations (Details) $ in Thousands	3 Months Ended	9 Months Ended	11 Months Ended
Jun. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2017 USD ($) property
Business Acquisition [Line Items]
Number of properties acquired \| property			8
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Depreciation expense related to purchase price allocation adjustments	$ 0	$ 784,000
Previously Acquired
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Total consideration	314,878	314,878	$ 314,878
Adjustments, consideration transferred		0
Previously Acquired \| Land
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Real estate property	34,193	34,193	34,193
Adjustments, property, plant and equipment		(1,550)
Previously Acquired \| Buildings and Improvements
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Real estate property	276,463	276,463	276,463
Adjustments, property, plant and equipment		341
Previously Acquired \| Scenario, Previously Reported
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Total consideration	314,878	314,878	314,878
Previously Acquired \| Scenario, Previously Reported \| Land
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Real estate property	35,743	35,743	35,743
Previously Acquired \| Scenario, Previously Reported \| Buildings and Improvements
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Real estate property	276,122	276,122	276,122
Acquisition-related intangible assets \| Previously Acquired
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Acquisition-related intangibles	4,222	4,222	4,222
Adjustments, acquisition-related intangible assets		1,209
Acquisition-related intangible assets \| Previously Acquired \| Scenario, Previously Reported
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Acquisition-related intangibles	$ 3,013	$ 3,013	$ 3,013

Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Depreciation

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.

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- Definition

This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to items of consideration transferred in connection with a business combination for which the initial accounting was incomplete.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 4A
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84161108&loc=SL65897772-128472

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- Definition

This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to intangibles acquired in connection with a business combination for which the initial accounting was incomplete.

+ References

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- Definition

This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to property, plant, and equipment acquired in connection with a business combination for which the initial accounting was incomplete.

+ References

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- Definition

The amount of identifiable intangible assets recognized as of the acquisition date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 55
-Paragraph 37
-URI http://asc.fasb.org/extlink&oid=84160947&loc=d3e2207-128464

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-Paragraph 1
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- Definition

Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

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The amount of property, plant, and equipment recognized as of the acquisition date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
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- Definition

The number of businesses acquired by the entity during the period.

+ References

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