Derivative Instruments and Hedging Activities - Summary of Fair Value of Interest Rate Swaps (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Derivative [Line Items]
Interest rate swap assets	$ 29,884	$ 9,855
Interest rate swap liabilities		317
Designated as Hedging Instrument [Member] \| Cash Flow Hedges [Member] \| Other Assets [Member]
Derivative [Line Items]
Interest rate swap assets	$ 29,884	9,855
Designated as Hedging Instrument [Member] \| Cash Flow Hedges [Member] \| Interest Rate Swap [Member]
Derivative [Line Items]
Interest rate swap liabilities		$ 317

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13433-108611

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- Definition

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

+ References

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