Real Estate Properties - Property Acquisition, Purchase Price Allocation (Details) (Series Of Real Estate Property Acquisitions Year2014 [Member], USD $) In Thousands, unless otherwise specified	6 Months Ended
Mar. 31, 2015
Allocation of purchase prices of assets acquired and liabilities assumed
Total consideration	$ 55,420
Adjustments to preliminary allocations of purchase price of properties
Total consideration	0
Scenario, Previously Reported [Member]
Allocation of purchase prices of assets acquired and liabilities assumed
Total consideration	55,420
Building and Building Improvements [Member]
Allocation of purchase prices of assets acquired and liabilities assumed
Real estate property	33,770
Adjustments to preliminary allocations of purchase price of properties
Real estate property	(326)
Building and Building Improvements [Member] \| Scenario, Previously Reported [Member]
Allocation of purchase prices of assets acquired and liabilities assumed
Real estate property	34,096
Land [Member]
Allocation of purchase prices of assets acquired and liabilities assumed
Real estate property	21,263
Adjustments to preliminary allocations of purchase price of properties
Real estate property	(61)
Land [Member] \| Scenario, Previously Reported [Member]
Allocation of purchase prices of assets acquired and liabilities assumed
Real estate property	21,324
Leases Acquired In Place Including Market Adjustment, Intangible Assets, Gross [Member]
Allocation of purchase prices of assets acquired and liabilities assumed
Acquisition related intangibles	387
Adjustments to preliminary allocations of purchase price of properties
Acquisition related intangibles	387
Leases Acquired In Place Including Market Adjustment, Intangible Assets, Gross [Member] \| Scenario, Previously Reported [Member]
Allocation of purchase prices of assets acquired and liabilities assumed
Acquisition related intangibles	$ 0

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 10

-Section 50

-Paragraph 6

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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.

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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 20

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=56956791&loc=d3e4845-128472

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-Topic 805

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-Section 55

-Paragraph 37

-URI http://asc.fasb.org/extlink&oid=35744172&loc=d3e2207-128464

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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.

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