Real Estate Properties - Assets Acquired and Liabilities Assumed (Details) $ in Thousands	9 Months Ended
Jun. 30, 2016 USD ($)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Total consideration	$ 89,150
Previously Acquired
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Total consideration	210,800
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustments [Abstract]
Total consideration	0
Acquisition-related intangible assets (in acquired lease intangibles, net) \| Previously Acquired
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Acquisition-related intangibles	975
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustments [Abstract]
Acquisition-related intangibles	643
Adjustments \| Previously Acquired
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Total consideration	210,800
Adjustments \| Acquisition-related intangible assets (in acquired lease intangibles, net) \| Previously Acquired
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Acquisition-related intangibles	332
Land
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Real estate property	18,875
Land \| Previously Acquired
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Real estate property	23,826
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustments [Abstract]
Real estate property	(4,730)
Land \| Adjustments \| Previously Acquired
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Real estate property	28,556
Buildings and Improvements
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Real estate property	69,688
Buildings and Improvements \| Previously Acquired
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Real estate property	185,999
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustments [Abstract]
Real estate property	4,087
Buildings and Improvements \| Adjustments \| Previously Acquired
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Real estate property	181,912
Indefinite-lived Intangible Assets
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net [Abstract]
Acquisition-related intangibles	$ 587

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.

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=73530397&loc=SL65897772-128472

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- 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

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- 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

+ Details

Name:	us-gaap_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentPropertyPlantAndEquipment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- References

No definition available.

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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=73531372&loc=d3e2207-128464

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=73530397&loc=d3e4845-128472

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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

+ References

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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- References

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
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- Definition

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)
-URI http://asc.fasb.org/extlink&oid=73530397&loc=d3e4845-128472

Reference 2: 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=73531372&loc=d3e2207-128464

+ Details

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- Details

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- Details

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