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Derivative Instruments (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2017 | Sep. 30, 2016 | Sep. 30, 2017 | Sep. 30, 2016
Effects of derivative instruments |  |  |  |
Amount of Gain Recognized in OCI on Derivatives (Effective Portion) | $ 458 | $ (2,547) | $ 780 | $ (2,021)
Cash Flow Hedging |  |  |  |
Effects of derivative instruments |  |  |  |
Amount of Gain Recognized in OCI on Derivatives (Effective Portion) | 164 |  | 160 |
Amount of Loss (Gain) Reclassified from Accumulated OCI into Income (Effective Portion) | 117 |  | 517 |
Cash Flow Hedging | Interest expense Member |  |  |  |
Effects of derivative instruments |  |  |  |
Amount of Loss (Gain) Reclassified from Accumulated OCI into Income (Effective Portion) | 117 |  | 517 |
Cash Flow Hedging | Interest rate contracts | Interest expense Member |  |  |  |
Effects of derivative instruments |  |  |  |
Amount of Gain Recognized in OCI on Derivatives (Effective Portion) | $ 164 |  | $ 160 |

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- Definition The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959 + Details
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