| **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** | Sep. 30, 2016 | Dec. 31, 2015 |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---------------|---------------|
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Available for sale securities                                                                                                                                                               | $ 675,813     | $ 658,400     |
| Significant Other Observable Inputs (Level 2)                                                                                                                                               |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Available for sale securities                                                                                                                                                               | 670,371       | 652,468       |
| Significant Unobservable Inputs (Level 3)                                                                                                                                                   |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Available for sale securities                                                                                                                                                               | 5,442         | 5,932         |
| 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                                                                                                                                                                | 16,535        | 8,070         |
| Fair Value, Measurements, Recurring | U.S. Government-sponsored agency securities | Significant Other Observable Inputs (Level 2)                                                           |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Available for sale securities                                                                                                                                                               | 101           | 104           |
| Fair Value, Measurements, Recurring | State and municipal | Significant Other Observable Inputs (Level 2)                                                                                   |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Available for sale securities                                                                                                                                                               | 363,643       | 300,014       |
| Fair Value, Measurements, Recurring | State and municipal | Significant Unobservable Inputs (Level 3)                                                                                       |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Available for sale securities                                                                                                                                                               | 5,407         | 5,897         |
| Fair Value, Measurements, Recurring | U.S. Government-sponsored mortgage-backed securities | Significant Other Observable Inputs (Level 2)                                                  |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Available for sale securities                                                                                                                                                               | 304,580       | 346,266       |
| Fair Value, Measurements, Recurring | Certificates of deposit | Significant Other Observable Inputs (Level 2)                                                                               |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Available for sale securities                                                                                                                                                               |          | 2,176         |
| Fair Value, Measurements, Recurring | Corporate obligations | Significant Unobservable Inputs (Level 3)                                                                                     |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Available for sale securities                                                                                                                                                               | 31            | 31            |
| Fair Value, Measurements, Recurring | Equity securities | Significant Other Observable Inputs (Level 2)                                                                                     |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Available for sale securities                                                                                                                                                               | 2,012         | 3,908         |
| Fair Value, Measurements, Recurring | Equity securities | Significant Unobservable Inputs (Level 3)                                                                                         |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Available for sale securities                                                                                                                                                               | 4             | 4             |
| Fair Value, Measurements, Recurring | Interest rate swap asset | Significant Other Observable Inputs (Level 2)                                                                              |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Interest rate derivatives                                                                                                                                                                   | 12,102        | 4,938         |
| Fair Value, Measurements, Recurring | Interest rate cap | Significant Other Observable Inputs (Level 2)                                                                                     |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Interest rate derivatives                                                                                                                                                                   | 4             | 36            |
| Fair Value, Measurements, Recurring | Fair Value | Interest rate swap liability                                                                                                             |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Interest rate swap liability                                                                                                                                                                | 16,535        | 8,070         |
| Fair Value, Measurements, Recurring | Fair Value | U.S. Government-sponsored agency securities                                                                                              |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Available for sale securities                                                                                                                                                               | 101           | 104           |
| Fair Value, Measurements, Recurring | Fair Value | State and municipal                                                                                                                      |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Available for sale securities                                                                                                                                                               | 369,050       | 305,911       |
| Fair Value, Measurements, Recurring | Fair Value | U.S. Government-sponsored mortgage-backed securities                                                                                     |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Available for sale securities                                                                                                                                                               | 304,580       | 346,266       |
| Fair Value, Measurements, Recurring | Fair Value | Certificates of deposit                                                                                                                  |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Available for sale securities                                                                                                                                                               |          | 2,176         |
| Fair Value, Measurements, Recurring | Fair Value | Corporate obligations                                                                                                                    |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Available for sale securities                                                                                                                                                               | 31            | 31            |
| Fair Value, Measurements, Recurring | Fair Value | Equity securities                                                                                                                        |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Available for sale securities                                                                                                                                                               | 2,016         | 3,912         |
| Fair Value, Measurements, Recurring | Fair Value | Interest rate swap asset                                                                                                                 |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Interest rate derivatives                                                                                                                                                                   | 12,102        | 4,938         |
| Fair Value, Measurements, Recurring | Fair Value | Interest rate cap                                                                                                                        |          |          |
| **Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]**                                                                                                           |          |          |
| Interest rate derivatives                                                                                                                                                                   | $ 4           | $ 36          |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.
+ 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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| - 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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