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Derivatives and Hedging Activities (Derivative Positions for Interest Rate Swaps which Qualify as Hedges) (Details) - USD ($) | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Details of derivative positions for interest rate swaps which qualify as hedges for accounting purposes |  |  |
Derivative, Cap Interest Rate | 3.02% |  |
Derivative, Floor Interest Rate | 2.51% |  |
Amortization Of Deferred Hedge Gains Losses | $ 231,000 | $ 244,000 | $ 244,000
Notional amount of fair value hedged derivative | $ 0 | $ 0 | $ 0
Interest rate swaps on borrowings [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Average Remaining Maturity | 3 years 2 months 4 days | 3 years 4 months 13 days |
Derivative, Average Variable Interest Rate | 2.74% | 1.54% |
Details of derivative positions for interest rate swaps which qualify as hedges for accounting purposes |  |  |
Notional Amount | $ 75,000,000 | $ 100,000,000 |
Fair Value | $ 2,282,000 | $ 1,616,000 |
Derivative, Average Fixed Interest Rate | 1.53% | 1.89% |
Interest rate swaps on loans [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Average Remaining Maturity | 4 years 6 months 7 days |  |
Derivative, Average Variable Interest Rate | 2.57% |  |
Details of derivative positions for interest rate swaps which qualify as hedges for accounting purposes |  |  |
Notional Amount | $ 250,000,000 |  |
Fair Value | $ 2,938,000 |  |
Derivative, Average Fixed Interest Rate | 2.67% |  |
Interest rate collars on loans [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Average Remaining Maturity | 4 years 2 months 1 day |  |
Derivative, Average Variable Interest Rate | 2.47% |  |
Details of derivative positions for interest rate swaps which qualify as hedges for accounting purposes |  |  |
Notional Amount | $ 250,000,000 |  |
Fair Value | 3,344,000 |  |
Interest Rate Swap [Member] |  |  |
Details of derivative positions for interest rate swaps which qualify as hedges for accounting purposes |  |  |
Notional Amount | 575,000,000 | $ 100,000,000 |
Fair Value | $ 8,564,000 | $ 1,616,000 |

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- Definition The amount of expense charged against earnings by an entity to record deferred gains and losses on hedge instruments. + References No definition available. + Details
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- Definition Aggregate notional amount specified by a fair value hedged derivative. + References No definition available. + Details
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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 Average cap rate on a group of interest rate derivatives, such as interest rate caps or collars. If market rates exceed the cap rate, a payment or receipt is triggered on the contract. + References No definition available. + Details
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- Definition Average fixed interest rate related to the group of interest rate derivatives. + References No definition available. + Details
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- Definition Average floor rate on a group of interest rate derivatives, such as interest rate floor or collars. If market rates fall below the floor rate, a payment or receipt is triggered on the contract. + References No definition available. + Details
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- Definition Average remaining period until maturity of the derivative contract, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition Fair value of the assets less the liabilities of a derivative or group of derivatives. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13433-108611 + Details
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