| **Derivative Financial Instruments - Fair Value of Derivative Financial Instruments and Their Classification on Balance Sheet (Details) - Interest rate contracts - USD ($) $ in Thousands** | Mar. 31, 2019 | Dec. 31, 2018 |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---------------|---------------|
| Derivatives designated as hedging instruments | Other Assets                                                                                                                                 |          |          |
| **Derivatives, Fair Value [Line Items]**                                                                                                                                                     |          |          |
| Asset Derivatives                                                                                                                                                                            | $ 35          | $ 135         |
| Derivatives designated as hedging instruments | Other Liabilities                                                                                                                            |          |          |
| **Derivatives, Fair Value [Line Items]**                                                                                                                                                     |          |          |
| Liability Derivatives                                                                                                                                                                        | 972           | 688           |
| Derivatives not designated as hedging instruments | Other Assets                                                                                                                             |          |          |
| **Derivatives, Fair Value [Line Items]**                                                                                                                                                     |          |          |
| Asset Derivatives                                                                                                                                                                            | 14,194        | 11,948        |
| Derivatives not designated as hedging instruments | Other Liabilities                                                                                                                        |          |          |
| **Derivatives, Fair Value [Line Items]**                                                                                                                                                     |          |          |
| Liability Derivatives                                                                                                                                                                        | $ 14,194      | $ 11,948      |

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| - Definition
Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.
+ References
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.
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| - Definition
Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
+ References
No definition available.
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