Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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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.

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- Definition

The number of derivative instruments of a particular group held by the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959

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- Definition

Fair value as of the balance sheet date of interest rate derivative assets, net of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized on the balance sheet.

+ References

No definition available.

+ Details

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Risk Management and Use of Derivative Financial Instruments - Interest Rate Swap and Swaptions Summary (Details) € in Thousands, £ in Thousands, $ in Thousands	Jun. 30, 2018 USD ($) instrument	Jun. 30, 2018 GBP (£) instrument	Jun. 30, 2018 EUR (€) instrument
Derivative
Fair value	$ (1,067)
Derivatives Designated as Hedging Instruments \| Interest rate swaps \| Euro
Derivative
Number of Instruments \| instrument	3	3	3
Notional Amount \| €			€ 65,982
Fair value	$ (728)
Derivatives Designated as Hedging Instruments \| Interest rate swaps \| USD
Derivative
Number of Instruments \| instrument	12	12	12
Notional Amount	$ 122,615
Fair value	$ (357)
Derivatives Designated as Hedging Instruments \| Interest rate cap \| Euro
Derivative
Number of Instruments \| instrument	4	4	4
Notional Amount \| €			€ 132,614
Fair value	$ 79
Derivatives Designated as Hedging Instruments \| Interest rate cap \| USD
Derivative
Number of Instruments \| instrument	1	1	1
Notional Amount	$ 75,000
Fair value	$ 58
Derivatives Designated as Hedging Instruments \| Interest rate cap \| GBP
Derivative
Number of Instruments \| instrument	1	1	1
Notional Amount \| £		£ 6,394
Fair value	$ 8
Not Designated as Hedging Instrument \| Interest rate swap \| Euro
Derivative
Number of Instruments \| instrument	1	1	1
Notional Amount \| €			€ 4,784
Fair value	$ (127)