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Derivative Instruments and Hedging Activities (Tables) | 6 Months Ended
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Jun. 30, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract] |
Value of Derivative Assets and Derivative Liabilities | The following table indicates the amounts representing the value of derivative assets and derivative liabilities as of the dates presented:
| Derivatives (included in Other Assets) |  | Derivatives (included in Other Liabilities)
(dollars in thousands) | June 30, 2017 |  | December 31, 2016 |  | June 30, 2017 |  | December 31, 2016
Derivatives not Designated as Hedging Instruments: |  |  |  |  |  |  |
Interest Rate Swap Contracts- Commercial Loans |  |  |  |  |  |  |
Fair value | $ | 5,442 |  |  | $ | 6,960 |  |  | $ | 5,423 |  |  | $ | 6,958 |
Notional amount | 228,298 |  |  | 232,396 |  |  | 228,298 |  |  | 232,396 |
Collateral posted | — |  |  | — |  |  | — |  |  | 14,340 |
Interest Rate Lock Commitments- Mortgage Loans |  |  |  |  |  |  |
Fair value | 456 |  |  | 236 |  |  | — |  |  | — |
Notional amount | 14,585 |  |  | 8,490 |  |  | — |  |  | — |
Forward Sale Contracts- Mortgage Loans |  |  |  |  |  |  |
Fair value | 14 |  |  | — |  |  | — |  |  | 27 |
Notional amount | $ | 13,911 |  |  | $ | — |  |  | $ | — |  |  | $ | 8,216 |
Schedule of Gross Amounts of Derivative Assets and Derivative Liabilities | The following table indicates the gross amounts of commercial loan swap derivative assets and derivative liabilities, the amounts offset and the carrying values in the Consolidated Balance Sheets as of the dates presented:
| Derivatives (included in Other Assets) |  | Derivatives (included in Other Liabilities)
(dollars in thousands) | June 30, 2017 |  | December 31, 2016 |  | June 30, 2017 |  | December 31, 2016
Derivatives not Designated as Hedging Instruments: |  |  |  |  |  |  |
Gross amounts recognized | $ | 6,811 |  |  | $ | 8,590 |  |  | $ | 6,792 |  |  | $ | 8,588 |
Gross amounts offset | (1,369 | ) |  | (1,630 | ) |  | (1,369 | ) |  | (1,630 | )
Net amounts presented in the Consolidated Balance Sheets | 5,442 |  |  | 6,960 |  |  | 5,423 |  |  | 6,958 |
Gross amounts not offset(1) | — |  |  | — |  |  | (3,939 | ) |  | (14,340 | )
Net Amount | $ | 5,442 |  |  | $ | 6,960 |  |  | $ | 1,484 |  |  | $ | (7,382 | )
(1) Amounts represent posted collateral.
Amount of Gain or Loss Recognized in Income on Derivatives | The following table indicates the gain or loss recognized in income on derivatives for the periods presented:
| Three Months Ended June 30, |  | Six Months Ended June 30,
(dollars in thousands) | 2017 |  | 2016 |  | 2017 |  | 2016
Derivatives not Designated as Hedging Instruments |  |  |  |  |  |  |
Interest rate swap contracts—commercial loans | $ | (8 | ) |  | $ | 23 |  |  | $ | 16 |  |  | $ | 120 |
Interest rate lock commitments—mortgage loans | (13 | ) |  | 117 |  |  | 220 |  |  | 382 |
Forward sale contracts—mortgage loans | 76 |  |  | (132 | ) |  | 40 |  |  | (199 | )
Total Derivatives Gain | $ | 55 |  |  | $ | 8 |  |  | $ | 276 |  |  | $ | 303 |

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