This element represents the number of buildings sold or agreed to be sold by the entity.

No definition available.

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- Definition

Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Publisher SEC
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+ Details

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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 50
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+ Details

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- Definition

The charge against earnings in the period to reduce the carrying amount of real property to fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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- Definition

Amount after tax of reclassification adjustments of other comprehensive income (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Real Estate Properties - Summary of Properties Disposed (Footnote) (Details) $ in Thousands	1 Months Ended			3 Months Ended		12 Months Ended
	May 31, 2015 USD ($) building	Mar. 31, 2015 building	Jan. 31, 2013 building	Jun. 30, 2015 building	May 31, 2015 USD ($) building	Dec. 31, 2016 USD ($) building	Dec. 31, 2015 USD ($) building	Dec. 31, 2014 USD ($) building
Real Estate Properties [Line Items]
Number of buildings sold \| building			18
Principal balance						$ 1,151,634	$ 1,711,666
(Loss) gain on early extinguishment of debt						$ (2,680)	6,661	$ 4,909
Impairment of real estate							17,200
Foreign Currency Translation Adjustments
Real Estate Properties [Line Items]
Amounts reclassified from cumulative other comprehensive loss to net income							$ (63,207)
Disposed of by Sale
Real Estate Properties [Line Items]
Number of buildings sold \| building						62	135	43
333 Laurel Oak Drive \| Disposed of by Sale
Real Estate Properties [Line Items]
Number of buildings sold \| building	2	1			3
225 Water Street \| Mortgage notes
Real Estate Properties [Line Items]
Principal balance	$ 40,100				$ 40,100
(Loss) gain on early extinguishment of debt							$ 17,300
Australia Portfolio \| Foreign Currency Translation Adjustments
Real Estate Properties [Line Items]
Amounts reclassified from cumulative other comprehensive loss to net income							$ (63,200)
Australia Portfolio \| Disposed of by Sale
Real Estate Properties [Line Items]
Number of buildings sold \| building				11