Real Estate (Real Estate Available and Held for Sale) (Details) $ in Thousands	9 Months Ended
Sep. 30, 2017 USD ($) lease_asset	Sep. 30, 2016 USD ($) lease_asset
Real Estate Properties [Line Items]
Acquisitions of real estate assets	$ 0	$ 4,740
Payments to acquire land		$ 3,900
Term of ground lease		99 years
Commercial Operating Properties
Real Estate Properties [Line Items]
Net lease asset transferred \| lease_asset	1
Residential Operating Properties
Real Estate Properties [Line Items]
Acquisitions of real estate assets	$ 800
Executed Contract with Third Party \| Net Lease
Real Estate Properties [Line Items]
Net lease asset transferred \| lease_asset	1	1
Property transferred to held for sale, carrying value	$ 900	$ 700
Executed Contract with Third Party \| Commercial Operating Properties
Real Estate Properties [Line Items]
Property transferred to held for sale, carrying value		$ 16,100

Number of Real Estate Properties Transferred to Held for Sale

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- Definition

Property Transferred to Held for Sale, Aggregate, Carrying Value

+ References

No definition available.

+ Details

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- Definition

Term of the lessor's leasing arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

The cash outflow from the acquisition of real estate intended to generate income for the owner; excludes land acquired for use by the owner.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3213-108585

+ Details

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- Definition

The cash outflow from the acquisition of a piece of land, anything permanently fixed to it, including buildings, structures on it and so forth; includes real estate intended to generate income for the owner; excludes real estate acquired for use by the owner.

+ References

+ Details

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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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