Derivative Instruments and Hedging Activities - Effects on statements of income and consolidated statements of comprehensive income (Details) - Interest Rate Swap - USD ($) $ in Thousands |
12 Months Ended | |||
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Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2013 |
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| Derivative Instruments, Gain (Loss) [Line Items] | ||||
| Amount of Gain Recognized in Net Income (Loss) | $ (266) | |||
| Designated as Hedging Instrument | ||||
| Derivative Instruments, Gain (Loss) [Line Items] | ||||
| Amount of Gain Recognized in Net Income (Loss) | $ (271) | $ (279) | $ (368) | |
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- Definition Amount of increase (decrease) in the fair value of derivatives recognized in the income statement. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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. No definition available.
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