Real Estate Activities Real Estate Activities - Acquisitions and Dispositions(Details) - USD ($) $ in Thousands		3 Months Ended
Feb. 16, 2018	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Real Estate Property Sale Price	$ 41,800
Proceeds from Real Estate and Real Estate Joint Ventures	$ 19,700
Deferred costs and other assets, net		$ 114,332		$ 112,046
Gains (Losses) on Sales of Investment Real Estate		$ 0	$ (57)
Gain (Loss) on Sale of Properties			$ (57)

Real Estate Property Sale Price

No definition available.

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- Definition

Amount of deferred cost assets and assets classified as other.

+ References

No definition available.

+ Details

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- Definition

The difference between the carrying value and the sale price of real estate or properties that were intended to be sold or held for capital appreciation or rental income. This element refers to the gain (loss) included in earnings and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

+ Details

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- Definition

The net gain (loss) resulting from sales and other disposals of real estate owned for investment purposes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.14(d))
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

+ Details

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- Definition

The cash inflow from the sale of real estate held-for-investment and real estate joint ventures.

+ References

No definition available.

+ 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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