Derivative Financial Instruments - Summary of Outstanding Non-designated Hedges (Detail) - Jun. 30, 2015 - Not Designated as Hedging Instrument [Member] - Interest Rate Caps [Member]	USD ($) DerivativeInstrument	GBP (£) DerivativeInstrument
USD [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Number of Instruments	2	2
Notional Amount \| $	$ 42,240,000
GBP [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Number of Instruments	1	1
Notional Amount \| £		£ 619,000

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.

+ Details

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- Definition

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

+ 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=56946850&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=56946850&loc=SL5579245-113959

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