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Derivatives - Additional Information (Detail) $ in Thousands | 12 Months Ended
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Dec. 31, 2019 USD ($) Derivative | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($)
Derivative [Line Items] |  |  |
Number of participation agreements for interest rate swaps, participant | Derivative | 31 |  |
Number of participation agreements for interest rate swaps, lead bank | Derivative | 12 |  |
Derivative, Gain (Loss) on Derivative, Net | $ (269) | $ 787 | $ (473)
Interest Rate Swap [Member] | Cash Flow Hedging [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Notional Amount | 70,000 | 65,000 |
Interest Rate Swap [Member] | Designated as Hedging Instrument [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Notional Amount | 70,000 | 65,000 |
Interest Rate Swap [Member] | Interest Income [Member] | Designated as Hedging Instrument [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Gain (Loss) on Derivative, Net | (118) | (590) | 452
Interest Rate Swap [Member] | Other Income [Member] | Designated as Hedging Instrument [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Gain (Loss) on Derivative, Net | (159) | 0 | 0
Foreign Exchange Contract [Member] | Designated as Hedging Instrument [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Notional Amount | 4,789 | 1,927 |
Derivative Liability, Fair Value, Gross Asset | 4,800 | 1,900 |
Foreign Exchange Contract [Member] | Other Income [Member] | Designated as Hedging Instrument [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Gain (Loss) on Derivative, Net | 5 | 15 | 4
Forward Contracts [Member] | Designated as Hedging Instrument [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Notional Amount | 30,000 | 15,000 |
Derivative, Underlying Asset Carrying Value | 9,800 | 6,900 |
Derivative Liability, Fair Value, Gross Asset | 10,700 | 7,600 |
Derivative Liability, Notional Amount | 25,500 | 9,900 |
Forward Contracts [Member] | Other Income [Member] | Designated as Hedging Instrument [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Gain (Loss) on Derivative, Net | 0 | (189) | (19)
Other Income | 106 | $ 0 | $ 0
2024 [Member] | Interest Rate Swap [Member] | Cash Flow Hedging [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Notional Amount | 30,000 |  |
2026 [Member] | Interest Rate Swap [Member] | Cash Flow Hedging [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Notional Amount | $ 40,000 |  |

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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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