| **Investment Securities - Narrative (Details) $ in Thousands**                             | Mar. 31, 2019 USD ($) security | Dec. 31, 2018 USD ($) |
|--------------------------------------------------------------------------------------------|--------------------------------|-----------------------|
| **Investments, Debt and Equity Securities [Abstract]**                                     |                           |                  |
| Carrying value of securities pledged as collateral                                         | $ 506,562                      | $ 416,155             |
| Book value of securities sold under agreements to repurchase                               | 112,029                        | 116,691               |
| **Schedule of Available for sale Securities and Held to maturity Securities [Line Items]** |                           |                  |
| Gross Unrealized Losses                                                                    | 3,672                          | 14,253                |
| Held-to-maturity unrealized losses                                                         | 1,704                          | $ 4,741               |
| State and municipal                                                                        |                           |                  |
| **Schedule of Available for sale Securities and Held to maturity Securities [Line Items]** |                           |                  |
| Gross Unrealized Losses                                                                    | $ 532                          |                  |
| Number of securities in unrealized loss positions | security                               | 33                             |                  |
| Held-to-maturity unrealized losses                                                         | $ 117                          |                  |
| Held-to-maturity, number of securities in unrealized loss positions | security             | 22                             |                  |
| U.S. Government-sponsored agency securities                                                |                           |                  |
| **Schedule of Available for sale Securities and Held to maturity Securities [Line Items]** |                           |                  |
| Gross Unrealized Losses                                                                    | $ 1                            |                  |
| Number of securities in unrealized loss positions | security                               | 1                              |                  |
| Held-to-maturity unrealized losses                                                         | $ 350                          |                  |
| Held-to-maturity, number of securities in unrealized loss positions | security             | 5                              |                  |
| U.S. Government-sponsored mortgage-backed securities                                       |                           |                  |
| **Schedule of Available for sale Securities and Held to maturity Securities [Line Items]** |                           |                  |
| Gross Unrealized Losses                                                                    | $ 3,139                        |                  |
| Number of securities in unrealized loss positions | security                               | 79                             |                  |
| Held-to-maturity unrealized losses                                                         | $ 1,237                        |                  |
| Held-to-maturity, number of securities in unrealized loss positions | security             | 45                             |                  |

| X                                                                                                                                                                                                                                                                                                                                                |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Schedule of Available for sale Securities and Held to maturity Securities [Line Items]
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| - Definition
Securities Pledged as Collateral
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Carrying amount of assets sold under agreements to repurchase when the carrying amount (or market value, if higher than the carrying amount) of securities or other assets sold under repurchase agreements exceeds 10 percent of total assets.
+ References
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| - Definition
Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on 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
Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position.
+ References
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| - Definition
Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity).
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| - Definition
Disclosure regarding factors used to determine that the impairment of securities categorized as held-to-maturity where cost exceeds fair value is not an other than temporary impairment (OTTI). This item contains disclosure of the number of investment positions in the held-to-maturity investments determined to be temporarily impaired.
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