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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- 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

Assertion that the amount of fair value hedge ineffectiveness is immaterial.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
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- 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=35706170&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=35706170&loc=SL5579245-113959

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- Details

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- Details

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Derivatives and Hedging Activity (Details) $ in Thousands	3 Months Ended		6 Months Ended
Derivatives and Hedging Activity (Details) $ in Thousands	Jun. 30, 2015 USD ($) instruments	Jun. 30, 2014	Jun. 30, 2015 USD ($) instruments	Jun. 30, 2014
Derivative [Line Items]
Ineffectiveness on Interest Rate Fair Value Hedges is Immaterial	0	3	0	3
Designated as Hedging Instrument [Member] \| Interest rate swaps [Member]
Derivative [Line Items]
Number instruments	9		9
Notional	$ 565,000		$ 565,000
Designated as Hedging Instrument [Member] \| Interest rate caps [Member]
Derivative [Line Items]
Number instruments	2		2
Notional	$ 219,984		$ 219,984
Not Designated as Hedging Instrument [Member] \| Interest rate caps [Member]
Derivative [Line Items]
Number instruments \| instruments	2		2
Notional	$ 116,289		$ 116,289