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Derivatives and Hedging Activities (FV of Derivative Financial Instruments and Classification on Balance Sheet) (Details) - USD ($) $ in Thousands | Sep. 30, 2020 | Dec. 31, 2019
--- | --- | ---
Derivatives, Fair Value [Line Items] |  |  |
Derivative Asset | [1] | $ 210,754 | $ 78,385
Derivative Liability | [2] | 132,625 | 53,923
Derivative Asset, Fair Value, Amount Offset Against Collateral | [1] | 156,707 | 53,503
Derivative, Collateral, Obligation to Return Securities | [1],[3] | 54,047 | 24,882
Derivative, Collateral, Right to Reclaim Securities | [2],[3] | 54,047 | 24,882
Derivative, Collateral, Obligation to Return Cash | [1] | 0 | 0
Derivative, Collateral, Right to Reclaim Cash | [2] | 73,094 | 25,493
Derivative Liability, Fair Value, Amount Offset Against Collateral | [2] | 5,484 | 3,548
Other Assets [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative Instruments Not Designated as Hedging Instruments, Asset, at Fair Value | [1] | 156,695 | 55,245
Derivative Asset, Fair Value, Gross Asset | [1] | 210,742 | 78,385
Other Liabilities [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative Instruments Not Designated as Hedging Instruments, Liability, at Fair Value | [2] | 150,052 | 53,726
Liability Derivatives | [2] | 151,613 | 53,923
Interest rate swaps [Member] | Derivatives designated as hedges [Member] | Other Assets [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Interest Rate Derivative Assets, at Fair Value | [1],[4] | 54,047 | 23,140
Interest rate swaps [Member] | Derivatives designated as hedges [Member] | Other Liabilities [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Interest Rate Derivative Liabilities, at Fair Value | [2],[5] | 1,561 | 197
Loan level swaps [Member] | Other Assets [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative Asset, Fair Value, Gross Asset | [1],[4] | 145,517 | 52,374
Loan level swaps [Member] | Other Liabilities [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Liability Derivatives | [2],[5] | 145,501 | 52,369
Foreign exchange contracts | Other Assets [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative Asset, Fair Value, Gross Asset | [1] | 3,785 | 1,191
Foreign exchange contracts | Other Liabilities [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Liability Derivatives | [2] | 3,759 | 1,149
Interest Rate Lock Commitments [Member] | Not Designated as Hedging Instrument | Other Assets [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative Instrument Not Designated as a Hedge, Interest Rate Lock Commitments, Asset at Fair Value | [1] | 6,587 | 1,680
Derivative Instrument Not Designated as a Hedge, Forward Sales Agreements, Asset at Fair Value | [1] | 61 | 0
Derivative Instrument Not Designated as a Hedge, Forward Sale Hedge Commitment, Asset at Fair Value | [1] | 0 | 0
Interest Rate Lock Commitments [Member] | Not Designated as Hedging Instrument | Other Liabilities [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative Instrument Not Designated as a Hedge, Interest Rate Lock Commitments, Liabilities at Fair Value | [2] | 0 | 0
Derivative Instrument Not Designated as a Hedge, Forward Sales Agreements, Liabilities at Fair Value | [2] | 0 | 12
Derivative Instrument Not Designated as a Hedge, Forward Sale Hedge Commitment, Liability at Fair Value | [2] | 523 | 196
CME [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Derivative, Collateral, Obligation to Return Cash | [1],[6] | (12) | 0
Derivative, Collateral, Right to Reclaim Cash | [2],[6] | 18,988 | 0
Risk Participation Agreement | Other Assets [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Credit Risk Derivative Assets, at Fair Value |  | 745 | 0
Risk Participation Agreement | Other Liabilities [Member] |  |  |
Derivatives, Fair Value [Line Items] |  |  |
Credit Risk Derivative Liabilities, at Fair Value |  | $ 269 | $ 0
[1] | All asset derivatives are located in other assets on the balance sheet.
[2] | All liability derivatives are located in other liabilities on the balance sheet.
[3] | Reflects offsetting derivative positions with the same counterparty that are not netted on the balance sheet.
[4] | Approximately $1.2 million and $1.9 million of accrued interest receivable is included in the fair value of the interest rate and loan level asset derivatives, respectively, as of September 30, 2020. Accrued interest receivable of approximately and $350,000 and $569,000 was excluded from the fair value of the interest rate and loan level asset derivatives, respectively, as of December 31, 2019.
[5] | Approximately $75,000 and $1.9 million of accrued interest payable is included in the fair value of the interest rate and loan level liability derivatives, respectively, as of September 30, 2020. Accrued interest payable of approximately $4,000 and $569,000 was excluded from the fair value of the interest rate and loan level derivative liabilities, respectively, as of December 31, 2019.
[6] | Netting adjustments represent the amounts recorded to convert derivative assets and liabilities cleared through CME from a gross basis to a net basis, inclusive of the variation margin payments, in accordance with applicable accounting guidance. As displayed in the table above, derivatives that cleared through the CME were either in a net asset position or a net liability position as of September 30, 2020.

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