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Derivatives and Hedging Activities (Derivative Positions for Interest Rate Swaps which Qualify as Hedges) (Details) - USD ($) | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019 | Dec. 31, 2019
Details of derivative positions for interest rate swaps which qualify as hedges for accounting purposes |  |  |  |  |  |
Amortization Of Deferred Hedge Gains Losses |  | $ 0 |  | $ 0 |  |
Change in Fair Value on Loans Held for Sale |  | 413,000 | $ 272,000 | 1,252,000 | $ 1,192,000 |
Fair Value Hedges, Net |  | 0 |  | 0 |  | $ 0
Interest rate collars on loans [Member] |  |  |  |  |  |
Details of derivative positions for interest rate swaps which qualify as hedges for accounting purposes |  |  |  |  |  |
Derivative, Notional Amount |  | $ 400,000,000 |  | $ 400,000,000 |  | $ 400,000,000
Derivative, Average Remaining Maturity |  |  |  | 2 years 10 months 28 days |  | 3 years 7 months 28 days
Derivative, Average Variable Interest Rate |  | 0.15% |  | 0.15% |  | 1.76%
Fair Value | [1] | $ 24,169,000 |  | $ 24,169,000 |  | $ 9,896,000
Derivative, Average Cap Interest Rate |  | 2.73% |  | 2.73% |  | 2.73%
Derivative, Average Floor Interest Rate |  | 2.20% |  | 2.20% |  | 2.02%
Interest rate swaps on loans [Member] |  |  |  |  |  |
Details of derivative positions for interest rate swaps which qualify as hedges for accounting purposes |  |  |  |  |  |
Derivative, Notional Amount |  | $ 450,000,000 |  | $ 450,000,000 |  | $ 450,000,000
Derivative, Average Remaining Maturity |  |  |  | 2 years 10 months 28 days |  | 3 years 7 months 28 days
Derivative, Average Variable Interest Rate |  | 0.15% |  | 0.15% |  | 1.76%
Derivative, Average Fixed Interest Rate |  | 2.37% |  | 2.37% |  | 2.37%
Fair Value | [1] | $ 29,878,000 |  | $ 29,878,000 |  | $ 12,907,000
Interest rate swaps on borrowings [Member] |  |  |  |  |  |
Details of derivative positions for interest rate swaps which qualify as hedges for accounting purposes |  |  |  |  |  |
Derivative, Notional Amount |  | $ 75,000,000 |  | $ 75,000,000 |  | $ 75,000,000
Derivative, Average Remaining Maturity |  |  |  | 1 year 5 months 4 days |  | 2 years 2 months 4 days
Derivative, Average Variable Interest Rate |  | 0.26% |  | 0.26% |  | 1.90%
Derivative, Average Fixed Interest Rate |  | 1.53% |  | 1.53% |  | 1.53%
Fair Value | [1] | $ (1,561,000) |  | $ (1,561,000) |  | $ 140,000
Interest rate swaps |  |  |  |  |  |
Details of derivative positions for interest rate swaps which qualify as hedges for accounting purposes |  |  |  |  |  |
Derivative, Notional Amount |  | 925,000,000 |  | 925,000,000 |  | 925,000,000
Fair Value | [1] | $ 52,486,000 |  | $ 52,486,000 |  | $ 22,943,000
[1] | Beginning in 2020, the Company made an election to include accrued interest within fair value balances.

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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 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 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=121572278&loc=d3e13433-108611 + Details
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