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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 | 12 Months Ended
--- | --- | ---
Mar. 31, 2021 | Mar. 31, 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 | $ (1,764) | $ 255 |
Fair Value Hedges, Net | 0 |  | $ 0
Interest Receivable | 33,400 | $ 25,900 |
Derivative, Net Liability Position, Aggregate Fair Value | 28,500 |  | 79,800
Exposure to Institutional Counterparties | 50,900 |  | 48,800
Exposure To Counterparties Relating To Customer Related Positions | 76,800 |  | 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
Derivative, Average Remaining Maturity | 2 years 4 months 28 days |  | 2 years 7 months 28 days
Derivative, Average Variable Interest Rate | 0.11% |  | 0.15%
Fair Value | $ 17,942 |  | $ 21,764
Derivative, Average Cap Interest Rate | 2.73% |  | 2.73%
Derivative, Average Floor Interest Rate | 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 |  | $ 450,000
Derivative, Average Remaining Maturity | 3 years 3 months 29 days |  | 2 years 7 months 28 days
Derivative, Average Variable Interest Rate | 0.10% |  | 0.15%
Derivative, Average Fixed Interest Rate | 2.16% |  | 2.37%
Fair Value | $ 21,467 |  | $ 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
Derivative, Average Remaining Maturity | 11 months 4 days |  | 1 year 2 months 4 days
Derivative, Average Variable Interest Rate | 0.19% |  | 0.22%
Derivative, Average Fixed Interest Rate | 1.53% |  | 1.53%
Fair Value | $ (1,075) |  | $ (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 |  | 925,000
Fair Value | 38,334 |  | 47,444
Interest Receivable | 1,200 |  | 1,200
Interest Payable, Current | $ (56) |  | $ (81)

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- Definition Change in Fair Value on Loans Held for Sale + References No definition available. + Details
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- Definition Exposure to counterparties relating to customer related positions. + References No definition available. + Details
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- Definition Exposure to Institutional Counterparties relating to the company's derivative portfolio. + 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 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 Average variable interest rate related to the group of interest rate derivatives. + 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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- 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=121590274&loc=SL5624258-113959 + Details
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- Definition Net fair value of all derivative instruments designated as fair value hedging instruments. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=117331979&loc=d3e41228-113958 + Details
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- Definition Carrying value as of the balance sheet date of [accrued] interest payable on all forms of debt, including trade payables, that has been incurred and is unpaid. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 45 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=121566466&loc=d3e7018-107765 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 45 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=121566466&loc=d3e6935-107765 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.20) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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- Definition Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.8) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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