Derivative And Hedging Activites - Summary of Fair Values of Derivative Instruments in the Company's Consolidated Balance Sheets (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Derivative Assets, Fair value	$ 9,978	$ 7,780
Derivative Liabilities, Fair value	8,354	5,961
Derivatives Designated as Hedging Instruments
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Derivative Assets, Fair value	1,881	1,970
Derivatives Designated as Hedging Instruments \| Interest Rate Contracts
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Derivative Assets, Notional amount	150,000	150,000
Derivatives Designated as Hedging Instruments \| Interest Rate Contracts \| Other Assets
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Derivative Assets, Fair value	1,881	1,970
Derivatives Not Designated as Hedging Instruments
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Derivative Assets, Fair value	8,097	5,810
Derivative Liabilities, Fair value	8,354	5,961
Derivatives Not Designated as Hedging Instruments \| Loan Related Derivative Contracts \| Interest Rate Swaps with Customers
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Derivative Assets, Notional amount	176,679	150,489
Derivatives Not Designated as Hedging Instruments \| Loan Related Derivative Contracts \| Interest Rate Swaps with Customers \| Other Assets
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Derivative Assets, Fair value	8,063	5,782
Derivatives Not Designated as Hedging Instruments \| Loan Related Derivative Contracts \| Mirror Swaps with Counterparties
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Derivative Liabilities, Notional Amount	176,679	150,489
Derivatives Not Designated as Hedging Instruments \| Loan Related Derivative Contracts \| Mirror Swaps with Counterparties \| Other Liabilities
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Derivative Liabilities, Fair value	8,063	5,782
Derivatives Not Designated as Hedging Instruments \| Loan Related Derivative Contracts \| Risk Participation Agreements Out to Counterparties
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Derivative Assets, Notional amount	19,000	19,000
Derivatives Not Designated as Hedging Instruments \| Loan Related Derivative Contracts \| Risk Participation Agreements Out to Counterparties \| Other Assets
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Derivative Assets, Fair value	34	28
Derivatives Not Designated as Hedging Instruments \| Loan Related Derivative Contracts \| Risk Participation Agreements with Counterparties
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Derivative Liabilities, Notional Amount	73,776	63,825
Derivatives Not Designated as Hedging Instruments \| Loan Related Derivative Contracts \| Risk Participation Agreements with Counterparties \| Other Liabilities
Derivative Instruments And Hedging Activities Disclosures [Line Items]
Derivative Liabilities, Fair value	$ 291	$ 179

Nominal or face amount used to calculate payments on the derivative asset.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Name Accounting Standards Codification
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