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Derivatives and Hedging Activities (Tables) | 9 Months Ended
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Sep. 30, 2019
Derivative Instruments and Hedging Activities Disclosure [Abstract] |
Schedule of Notional Amounts and Estimated Fair Values of Derivatives | The notional amounts and estimated fair values of the Company’s derivatives are presented in the following table. Fair value estimates are obtained from third parties and are based on pricing models.
| September 30, 2019 |  | December 31, 2018
| Notional Amount | Estimated Fair Value |  | Notional Amount | Estimated Fair Value
Derivative Assets (included in other assets on the consolidated balance sheets):
Non-hedging interest rate derivatives: |  |  |  |  |
Interest rate swap contracts | $ | 494.0 |  | $ | 30.8 |  |  | $ | 403.3 |  | $ | 8.8 |
Interest rate lock commitments | 122.4 |  | 2.0 |  |  | 51.0 |  | 1.3 |
Forward loan sales contracts | 174.7 |  | 0.2 |  |  | — |  | — |
Total derivative assets | $ | 791.1 |  | $ | 33.0 |  |  | $ | 454.3 |  | $ | 10.1 |
Derivative Liabilities (included in accounts payable and accrued expenses on the consolidated balance sheets):
Non-hedging interest rate derivatives: |  |  |  |  |
Interest rate swap contracts | $ | 494.0 |  | $ | 30.8 |  |  | $ | 403.3 |  | $ | 8.8 |
Forward loan sales contracts | — |  | — |  |  | 64.6 |  | 0.6 |
Total derivative liabilities | $ | 494.0 |  | $ | 30.8 |  |  | $ | 467.9 |  | $ | 9.4 |
Offsetting Assets and Liabilities | The following table illustrates the potential effect of the Company’s master netting arrangements, by type of financial instrument, on the Company’s consolidated balance sheets as of September 30, 2019 and December 31, 2018:
| September 30, 2019
| Gross Amounts Recognized |  | Gross Amounts Offset in the Balance Sheet |  | Net Amounts in the Balance Sheet |  | Financial Instruments |  | Fair Value of Financial Collateral in the Balance Sheet |  | Net Amount
Financial Assets
Interest rate swap contracts | $ | 30.8 |  |  | $ | — |  |  | $ | 30.8 |  |  | $ | 0.1 |  |  | $ | 19.7 |  |  | $ | 11.0 |
Mortgage related derivatives | 2.2 |  |  | — |  |  | 2.2 |  |  | — |  |  | — |  |  | 2.2 |
Total derivatives | 33.0 |  |  | — |  |  | 33.0 |  |  | 0.1 |  |  | 19.7 |  |  | 13.2 |
Total assets | $ | 33.0 |  |  | $ | — |  |  | $ | 33.0 |  |  | $ | 0.1 |  |  | $ | 19.7 |  |  | $ | 13.2 |
Financial Liabilities
Interest rate swap contracts | $ | 30.8 |  |  | $ | — |  |  | $ | 30.8 |  |  | $ | 0.1 |  |  | $ | — |  |  | $ | 30.7 |
Mortgage related derivatives | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Total derivatives | 30.8 |  |  | — |  |  | 30.8 |  |  | 0.1 |  |  | — |  |  | 30.7 |
Repurchase agreements | 636.9 |  |  | — |  |  | 636.9 |  |  | — |  |  | 636.9 |  |  | — |
Total liabilities | $ | 667.7 |  |  | $ | — |  |  | $ | 667.7 |  |  | $ | 0.1 |  |  | $ | 636.9 |  |  | $ | 30.7 |
| December 31, 2018
| Gross Amounts Recognized |  | Gross Amounts Offset in the Balance Sheet |  | Net Amounts in the Balance Sheet |  | Financial Instruments |  | Fair Value of Financial Collateral in the Balance Sheet |  | Net Amount
Financial Assets
Interest rate swap contracts | $ | 8.8 |  |  | $ | — |  |  | $ | 8.8 |  |  | $ | 2.7 |  |  | $ | 2.4 |  |  | $ | 3.7 |
Mortgage related derivatives | 1.3 |  |  | — |  |  | 1.3 |  |  | — |  |  | — |  |  | 1.3 |
Total derivatives | 10.1 |  |  | — |  |  | 10.1 |  |  | 2.7 |  |  | 2.4 |  |  | 5.0 |
Total assets | $ | 10.1 |  |  | $ | — |  |  | $ | 10.1 |  |  | $ | 2.7 |  |  | $ | 2.4 |  |  | $ | 5.0 |
Financial Liabilities
Interest rate swap contracts | $ | 8.8 |  |  | $ | — |  |  | $ | 8.8 |  |  | $ | 2.7 |  |  | $ | 4.1 |  |  | $ | 2.0 |
Mortgage related derivatives | 0.6 |  |  | — |  |  | 0.6 |  |  | — |  |  | — |  |  | 0.6 |
Total derivatives | 9.4 |  |  | — |  |  | 9.4 |  |  | 2.7 |  |  | 4.1 |  |  | 2.6 |
Repurchase agreements | 712.4 |  |  | — |  |  | 712.4 |  |  | — |  |  | 712.4 |  |  | — |
Total liabilities | $ | 721.8 |  |  | $ | — |  |  | $ | 721.8 |  |  | $ | 2.7 |  |  | $ | 716.5 |  |  | $ | 2.6 |
Schedule of Derivative Instruments, Effect on Other Comprehensive Income (Loss) | The following table presents the pre-tax gains or losses related to derivative contracts that were recorded in other non-interest income in the Company’s statements of income for the periods indicated:
| Three Months Ended September 30, |  | Nine Months Ended September 30,
| 2019 | 2018 |  | 2019 | 2018
Non-hedging interest rate derivatives: |  |  |  |  |
Amount of gain recognized in other non-interest income | $ | — |  | $ | 0.1 |  |  | $ | — |  | $ | 0.4 |
Amount of net fee income recognized in other non-interest income | 0.5 |  | — |  |  | 1.8 |  | 0.9 |
Amount of net gains recognized in mortgage banking revenues | 0.4 |  | — |  |  | 1.5 |  | — |

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