Derivative Contracts - Summary of Derivatives (Details) - Derivatives Designated as Cash Flow Hedges [Member] - Cash Flow Hedging [Member] - Interest Rate Swap [Member] $ in Thousands	Mar. 31, 2017 USD ($) instrument
Derivative [Line Items]
Number of Instruments \| instrument	22
Notional \| $	$ 2,985,480
Percent of notional amount related to the Fund	100.00%
Unconsolidated Funds [Member]
Derivative [Line Items]
Number of Instruments \| instrument	2
Notional \| $	$ 435,000
Percent of notional amount related to the Fund	100.00%

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

+ Details

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Period Type:	instant

- Definition

Equity Method Investment, Summarized Financial Information, Percentage Of Notional Amount Of Derivative

+ 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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Balance Type:	na
Period Type:	duration

- Definition

Number of interest rate derivative instruments held by the entity at the reporting date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5579245-113959

+ 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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