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Derivative Instruments - Cash flow hedges (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018
Effects of derivative instruments |  |  |  |
Amount of (Loss) Gain Recognized in OCI on Derivatives (Effective Portion) | $ (1,458) | $ (433) | $ (1,718) | $ 1,183
Cash Flow Hedging |  |  |  |
Effects of derivative instruments |  |  |  |
Amount of (Loss) Gain Recognized in OCI on Derivatives (Effective Portion) | (1,071) | 384 | (1,684) | 1,415
Amount of Gain Recognized from Accumulated OCI into Income (Effective Portion) | 194 | 94 | 397 | 69
Cash Flow Hedging | Interest rate contract |  |  |  |
Effects of derivative instruments |  |  |  |
Amount of (Loss) Gain Recognized in OCI on Derivatives (Effective Portion) | (1,071) | 384 | (1,684) | 1,415
Cash Flow Hedging | Interest rate contract | Interest expense |  |  |  |
Effects of derivative instruments |  |  |  |
Amount of Gain Recognized from Accumulated OCI into Income (Effective Portion) | $ 194 | $ 94 | $ 397 | $ 69

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- Definition The effective portion of gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments. + References No definition available. + Details
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