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Derivatives and Hedging Activities (Derivative Positions for Interest Rate Swaps which Qualify as Hedges) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2021 | Jun. 30, 2020 | Jun. 30, 2021 | Jun. 30, 2020 | Dec. 31, 2020
Details of derivative positions for interest rate swaps which qualify as hedges for accounting purposes |  |  |  |  |
Change in Fair Value on Loans Held for Sale | $ 305 | $ 583 | $ (1,459) | $ 839 |
Fair Value Hedges, Net | 0 |  | 0 |  | $ 0
Interest Receivable | 29,900 | $ 32,900 | 29,900 | $ 32,900 |
Derivative, Net Liability Position, Aggregate Fair Value | 42,200 |  | 42,200 |  | 79,800
Exposure to Institutional Counterparties | 40,500 |  | 40,500 |  | 48,800
Exposure To Counterparties Relating To Customer Related Positions | 81,700 |  | 81,700 |  | 127,200
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 |  | $ 400,000 |  | $ 400,000
Derivative, Average Remaining Maturity |  |  | 2 years 2 months 1 day |  | 2 years 7 months 28 days
Derivative, Average Variable Interest Rate | 0.08% |  | 0.08% |  | 0.15%
Fair Value | $ 15,964 |  | $ 15,964 |  | $ 21,764
Derivative, Average Cap Interest Rate | 2.73% |  | 2.73% |  | 2.73%
Derivative, Average Floor Interest Rate | 2.20% |  | 2.20% |  | 2.20%
Interest rate swaps on loans [Member] |  |  |  |  |
Details of derivative positions for interest rate swaps which qualify as hedges for accounting purposes |  |  |  |  |
Derivative, Notional Amount | $ 550,000 |  | $ 550,000 |  | $ 450,000
Derivative, Average Remaining Maturity |  |  | 3 years 29 days |  | 2 years 7 months 28 days
Derivative, Average Variable Interest Rate | 0.09% |  | 0.09% |  | 0.15%
Derivative, Average Fixed Interest Rate | 2.16% |  | 2.16% |  | 2.37%
Fair Value | $ 20,985 |  | $ 20,985 |  | $ 27,021
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 |  | $ 75,000 |  | $ 75,000
Derivative, Average Remaining Maturity |  |  | 8 months 4 days |  | 1 year 2 months 4 days
Derivative, Average Variable Interest Rate | 0.13% |  | 0.13% |  | 0.22%
Derivative, Average Fixed Interest Rate | 1.53% |  | 1.53% |  | 1.53%
Fair Value | $ (845) |  | $ (845) |  | $ (1,341)
Interest rate swaps |  |  |  |  |
Details of derivative positions for interest rate swaps which qualify as hedges for accounting purposes |  |  |  |  |
Derivative, Notional Amount | 1,025,000 |  | 1,025,000 |  | 925,000
Fair Value | 36,104 |  | 36,104 |  | 47,444
Interest Receivable | 1,200 |  | 1,200 |  | 1,200
Interest Payable, Current | $ (58) |  | $ (58) |  | $ (81)

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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 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 The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4H -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5624258-113959 + Details
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