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Derivative Financial Instruments (Narrative) (Details) $ in Thousands | 1 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Mar. 31, 2016 USD ($) contract | Jul. 31, 2009 USD ($) contract | Jun. 30, 2018 USD ($) | Dec. 31, 2017 USD ($)
Derivative [Line Items] |  |  |  |
Gain on derivative |  |  | $ 755 |
Increase in fair value of derivatives |  |  | 755 |
Deferred tax asset on gain on derivative |  |  | $ 204 |
Cash flow hedge ineffectiveness |  |  | 0 |
Interest Rate Swap [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Interest rate swap notional amount | $ 30,000 | $ 20,000 |  |
Number of interest rate swap contracts | contract | 4 | 3 |  |
Interest rate swap fair value |  |  | $ 1,500 | $ 800
Swap Contract - 3-Year $5 million [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Interest rate swap notional amount | $ 5,000 |  |  |
Derivative, maturity date | Jun. 17, 2019 |  |  |
Swap Contract - 5-Year $5 million [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Interest rate swap notional amount | $ 5,000 |  |  |
Derivative, maturity date | Mar. 17, 2021 |  |  |
Swap Contract - 10-Year $15 million [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Interest rate swap notional amount | $ 15,000 |  |  |
Derivative, maturity date | Mar. 17, 2026 |  |  |
Swap Contract- 7 year $5 Million [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Interest rate swap notional amount | $ 5,000 |  |  |
Derivative, maturity date | Mar. 17, 2023 |  |  |

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- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + References 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 + Details
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- Definition A disclosure of an assertion that the amount of cash flow hedge ineffectiveness is immaterial. + 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 (d)(1) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959 + Details
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from derivative instruments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 25 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=96869850&loc=d3e28680-109314 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32621-109319 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32632-109319 + Details
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- Definition Fair value of liability associated with financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=82849420&loc=SL20226003-175313 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4B -Subparagraph (a),(c) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624163-113959 + Details
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- Definition Amount of increase in the fair value of derivatives recognized in the income statement. + 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 (a),(c),(d),(e) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5618551-113959 + Details
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- Definition Date the derivative contract matures, in CCYY-MM-DD format. + References No definition available. + Details
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