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Interest-Rate Swaps (Details) - USD ($) $ in Thousands | 6 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2017 | Dec. 31, 2016
Derivative [Line Items] |  |
Weighted average pay rate on interest-rate swaps | 4.37% | 4.34%
Weighted average receive rate on interest-rate swaps | 3.51% | 3.04%
Weighted average maturity (years) | 4 years 6 months | 4 years 9 months 18 days
Fair value of combined interest-rate swaps | $ 587 | $ 685
Interest rate swaps |  |
Derivative [Line Items] |  |
Notional amounts | $ 31,542 | $ 34,360

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- Definition Fair value as of the balance sheet date of interest rate derivative assets, net of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized on the balance sheet. + 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 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13495-108611 + Details
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