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Derivatives - Additional Information (Detail) $ in Thousands | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2019 USD ($) Derivatives | Jun. 30, 2018 USD ($) | Jun. 30, 2019 USD ($) Derivatives | Jun. 30, 2018 USD ($) | Dec. 31, 2018 USD ($)
Risk participation Agreements [Line Items] |  |  |  |  |
Derivative, Net Hedge Ineffectiveness Gain (Loss) | $ 0 | $ (653) |  |  |
Derivative, Gain (Loss) on Derivative, Net | $ (17) | 0 | $ (43) | $ 789 |
Risk Participation Agreements Purchased [Domain] |  |  |  |  |
Risk participation Agreements [Line Items] |  |  |  |  |
Number of interest rate swaps | Derivatives | 35 |  | 35 |  |
Risk Participation Agreements Sold [Domain] |  |  |  |  |
Risk participation Agreements [Line Items] |  |  |  |  |
Number of interest rate swaps | Derivatives | 11 |  | 11 |  |
Forward Contracts [Member] |  |  |  |  |
Risk participation Agreements [Line Items] |  |  |  |  |
Derivative, Net Hedge Ineffectiveness Gain (Loss) | $ 0 | 33 | $ 0 | (29) |
Derivative Liability, Cost Basis, Gross Asset | 17,800 |  | 17,800 |  | $ 6,900
Derivative Liability, Fair Value, Gross Asset | 19,200 |  | 19,200 |  | 7,600
Derivative Liability, Notional Amount, Gross Asset | 28,000 |  | 28,000 |  | 9,900
Derivative, Gain (Loss) on Derivative, Net | (15) | 0 | (79) | 0 |
Forward Contracts [Member] | Designated as Hedging Instrument [Member] |  |  |  |  |
Risk participation Agreements [Line Items] |  |  |  |  |
Derivative, Fair Value, Net | 249 |  | 249 |  | 170
Derivative, Notional Amount | 33,000 |  | 33,000 |  | 15,000
Interest Rate Contract [Member] |  |  |  |  |
Risk participation Agreements [Line Items] |  |  |  |  |
Derivative, Net Hedge Ineffectiveness Gain (Loss) |  |  | 0 | (653) |
Foreign Exchange [Member] |  |  |  |  |
Risk participation Agreements [Line Items] |  |  |  |  |
Derivative, Net Hedge Ineffectiveness Gain (Loss) | (1) | 11 | 1 | 8 |
Foreign Exchange Contract [Member] | Designated as Hedging Instrument [Member] |  |  |  |  |
Risk participation Agreements [Line Items] |  |  |  |  |
Derivative, Fair Value, Net | 16 |  | 16 |  | 6
Derivative, Notional Amount | 4,601 |  | 4,601 |  | 1,927
Derivative Liability, Cost Basis, Gross Asset | 4,600 |  | 4,600 |  | 1,900
Derivative Liability, Fair Value, Gross Asset | 4,600 |  | 4,600 |  | 1,900
Interest Rate Swap [Member] |  |  |  |  |
Risk participation Agreements [Line Items] |  |  |  |  |
Derivative Instruments Designated As Hedging Instruments Interest Income | 0 | (150) | (118) | (231) |
Derivative, Net Hedge Ineffectiveness Gain (Loss) | 0 | $ 10 | 7 | $ 10 |
Interest Rate Swap [Member] | Designated as Hedging Instrument [Member] |  |  |  |  |
Risk participation Agreements [Line Items] |  |  |  |  |
Derivative, Fair Value, Net | 0 |  | 0 |  | 133
Derivative, Notional Amount | $ 0 |  | $ 0 |  | $ 65,000

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- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column B + Details
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