Derivatives and Hedging Activities - Schedule of Interest Rate Derivatives (Details) $ in Thousands	Dec. 31, 2017 USD ($) derivative	Dec. 31, 2016 USD ($) derivative
Cash Flow Hedging [Member]
Derivative [Line Items]
Notional Amount	$ 27,800
Designated as Hedging Instrument [Member] \| Interest Rate Swap [Member] \| Cash Flow Hedging [Member]
Derivative [Line Items]
Number of Instruments \| derivative	0	14
Notional Amount	$ 0	$ 690,816
Not Designated as Hedging Instrument [Member] \| Interest Rate Swap [Member]
Derivative [Line Items]
Number of Instruments \| derivative	2	1
Notional Amount	$ 78,949	$ 51,400

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

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=84234895&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=84234895&loc=SL5579245-113959

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- Details

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- Details

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