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Derivatives and Hedging Activities (Derivative Positions for Interest Rate Swaps which Qualify as Hedges) (Details) - USD ($) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2019 | Mar. 31, 2018 | Dec. 31, 2018
Details of derivative positions for interest rate swaps which qualify as hedges for accounting purposes |  |  |
Amortization Of Deferred Hedge Gains Losses | $ 0 | $ 61,000 |
Change in Fair Value on Loans Held for Sale | 1,000 | $ (26,000) |
Notional amount of fair value hedged derivative | $ 0 |  | $ 0
Interest rate collars on loans [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Average Cap Interest Rate | 3.02% |  | 3.02%
Details of derivative positions for interest rate swaps which qualify as hedges for accounting purposes |  |  |
Notional Amount | $ 250,000,000 |  | $ 250,000,000
Derivative, Average Remaining Maturity | 3 years 11 months 1 day |  | 4 years 2 months 1 day
Derivative, Average Variable Interest Rate | 2.49% |  | 2.47%
Fair Value | $ 5,150,000 |  | $ 3,344,000
Derivative, Average Floor Interest Rate | 2.51% |  | 2.51%
Interest rate swaps on loans [Member] |  |  |
Details of derivative positions for interest rate swaps which qualify as hedges for accounting purposes |  |  |
Notional Amount | $ 350,000,000 |  | $ 250,000,000
Derivative, Average Remaining Maturity | 4 years 2 months 23 days |  | 4 years 6 months 7 days
Derivative, Average Variable Interest Rate | 2.50% |  | 2.57%
Derivative, Average Fixed Interest Rate | 2.57% |  | 2.67%
Fair Value | $ 6,458,000 |  | $ 2,938,000
Interest rate swaps on borrowings [Member] |  |  |
Details of derivative positions for interest rate swaps which qualify as hedges for accounting purposes |  |  |
Notional Amount | $ 75,000,000 |  | $ 75,000,000
Derivative, Average Remaining Maturity | 2 years 11 months 4 days |  | 3 years 2 months 4 days
Derivative, Average Variable Interest Rate | 2.63% |  | 2.74%
Derivative, Average Fixed Interest Rate | 1.53% |  | 1.53%
Fair Value | $ 1,528,000 |  | $ 2,282,000
Interest rate swaps |  |  |
Details of derivative positions for interest rate swaps which qualify as hedges for accounting purposes |  |  |
Notional Amount | 675,000,000 |  | 575,000,000
Fair Value | $ 13,136,000 |  | $ 8,564,000

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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 Change in Fair Value on Loans Held for Sale + 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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- 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. + References No definition available. + Details
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