| **Disclosures About Fair Value of Assets and Liabilities - Fair Value Measurements of Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands** | Mar. 31, 2019 | Dec. 31, 2018 |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---------------|---------------|
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Investment securities available for sale                                                                                                                                                    | $ 1,247,632   | $ 1,142,195   |
| Quoted Prices in Active Markets for Identical Assets (Level 1)                                                                                                                              |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Investment securities available for sale                                                                                                                                                    | 0             | 0             |
| Significant Other Observable Inputs (Level 2)                                                                                                                                               |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Investment securities available for sale                                                                                                                                                    | 1,244,697     | 1,138,867     |
| Significant Unobservable Inputs (Level 3)                                                                                                                                                   |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Investment securities available for sale                                                                                                                                                    | 2,936         | 3,328         |
| Fair Value, Measurements, Recurring | Interest rate swap liability | Quoted Prices in Active Markets for Identical Assets (Level 1)                                                         |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Interest rate swap liability                                                                                                                                                                | 0             | 0             |
| Fair Value, Measurements, Recurring | Interest rate swap liability | Significant Other Observable Inputs (Level 2)                                                                          |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Interest rate swap liability                                                                                                                                                                | 15,166        | 12,636        |
| Fair Value, Measurements, Recurring | Interest rate swap liability | Significant Unobservable Inputs (Level 3)                                                                              |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Interest rate swap liability                                                                                                                                                                | 0             | 0             |
| Fair Value, Measurements, Recurring | Fair Value | Interest rate swap liability                                                                                                             |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Interest rate swap liability                                                                                                                                                                | 15,166        | 12,636        |
| U.S. Government-sponsored agency securities                                                                                                                                                 |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Investment securities available for sale                                                                                                                                                    | 33,703        | 13,582        |
| U.S. Government-sponsored agency securities | Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)                                          |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Investment securities available for sale                                                                                                                                                    | 0             | 0             |
| U.S. Government-sponsored agency securities | Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2)                                                           |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Investment securities available for sale                                                                                                                                                    | 33,703        | 13,582        |
| U.S. Government-sponsored agency securities | Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3)                                                               |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Investment securities available for sale                                                                                                                                                    | 0             | 0             |
| U.S. Government-sponsored agency securities | Fair Value, Measurements, Recurring | Fair Value                                                                                              |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Investment securities available for sale                                                                                                                                                    | 33,703        | 13,582        |
| State and municipal                                                                                                                                                                         |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Investment securities available for sale                                                                                                                                                    | 651,858       | 606,135       |
| State and municipal | Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)                                                                  |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Investment securities available for sale                                                                                                                                                    | 0             | 0             |
| State and municipal | Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2)                                                                                   |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Investment securities available for sale                                                                                                                                                    | 648,957       | 602,842       |
| State and municipal | Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3)                                                                                       |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Investment securities available for sale                                                                                                                                                    | 2,901         | 3,293         |
| State and municipal | Fair Value, Measurements, Recurring | Fair Value                                                                                                                      |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Investment securities available for sale                                                                                                                                                    | 651,858       | 606,135       |
| U.S. Government-sponsored mortgage-backed securities                                                                                                                                        |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Investment securities available for sale                                                                                                                                                    | 562,040       | 522,447       |
| U.S. Government-sponsored mortgage-backed securities | Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)                                 |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Investment securities available for sale                                                                                                                                                    | 0             | 0             |
| U.S. Government-sponsored mortgage-backed securities | Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2)                                                  |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Investment securities available for sale                                                                                                                                                    | 562,036       | 522,443       |
| U.S. Government-sponsored mortgage-backed securities | Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3)                                                      |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Investment securities available for sale                                                                                                                                                    | 4             | 4             |
| U.S. Government-sponsored mortgage-backed securities | Fair Value, Measurements, Recurring | Fair Value                                                                                     |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Investment securities available for sale                                                                                                                                                    | 562,040       | 522,447       |
| Corporate obligations                                                                                                                                                                       |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Investment securities available for sale                                                                                                                                                    | 31            | 31            |
| Corporate obligations | Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)                                                                |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Investment securities available for sale                                                                                                                                                    | 0             | 0             |
| Corporate obligations | Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2)                                                                                 |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Investment securities available for sale                                                                                                                                                    | 0             | 0             |
| Corporate obligations | Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3)                                                                                     |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Investment securities available for sale                                                                                                                                                    | 31            | 31            |
| Corporate obligations | Fair Value, Measurements, Recurring | Fair Value                                                                                                                    |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Investment securities available for sale                                                                                                                                                    | 31            | 31            |
| Interest rate swap asset | Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)                                                             |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Interest rate derivatives                                                                                                                                                                   | 0             | 0             |
| Interest rate swap asset | Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2)                                                                              |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Interest rate derivatives                                                                                                                                                                   | 14,194        | 11,948        |
| Interest rate swap asset | Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3)                                                                                  |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Interest rate derivatives                                                                                                                                                                   | 0             | 0             |
| Interest rate swap asset | Fair Value, Measurements, Recurring | Fair Value                                                                                                                 |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Interest rate derivatives                                                                                                                                                                   | 14,194        | 11,948        |
| Interest rate cap | Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)                                                                    |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Interest rate derivatives                                                                                                                                                                   | 0             | 0             |
| Interest rate cap | Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2)                                                                                     |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Interest rate derivatives                                                                                                                                                                   | 35            | 135           |
| Interest rate cap | Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3)                                                                                         |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Interest rate derivatives                                                                                                                                                                   | 0             | 0             |
| Interest rate cap | Fair Value, Measurements, Recurring | Fair Value                                                                                                                        |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Interest rate derivatives                                                                                                                                                                   | $ 35          | $ 135         |

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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).
+ References
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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.
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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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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.
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No definition available.
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