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Derivatives - Additional Information (Detail) $ in Thousands | 12 Months Ended
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Dec. 31, 2020 USD ($) Derivative | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($)
Derivative [Line Items] |  |  |
Number of participation agreements for interest rate swaps, participant | Derivative | 36 |  |
Number of participation agreements for interest rate swaps, lead bank | Derivative | 14 |  |
Derivative, Gain (Loss) on Derivative, Net | $ (2,521) | $ (269) | $ 787
Interest Rate Swap [Member] | Cash Flow Hedging [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Notional Amount | 70,000 | 70,000 |
Interest Rate Swap [Member] | Designated as Hedging Instrument [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Notional Amount | 70,000 | 70,000 |
Interest Rate Swap [Member] | Interest Income [Member] | Designated as Hedging Instrument [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Gain (Loss) on Derivative, Net | 0 | (118) | (590)
Interest Rate Swap [Member] | Other Income [Member] | Designated as Hedging Instrument [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Gain (Loss) on Derivative, Net | 449 | (159) | 0
Foreign Exchange Contract [Member] | Designated as Hedging Instrument [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative Liability, Fair Value, Gross Asset | 2,100 | 4,800 |
Derivative, Notional Amount | 2,119 | 4,789 |
Foreign Exchange Contract [Member] | Other Income [Member] | Designated as Hedging Instrument [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Gain (Loss) on Derivative, Net | 18 | 5 | 15
Forward Contracts [Member] | Designated as Hedging Instrument [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Underlying Asset Carrying Value | 25,000 | 9,800 |
Derivative Liability, Fair Value, Gross Asset | 28,400 | 10,700 |
Derivative Liability, Notional Amount | 47,900 | 25,500 |
Derivative, Notional Amount | 65,000 | 30,000 |
Forward Contracts [Member] | Other Income [Member] | Designated as Hedging Instrument [Member] |  |  |
Derivative [Line Items] |  |  |
Derivative, Gain (Loss) on Derivative, Net | 0 | 0 | (189)
Other Income | 420 | $ 106 | $ 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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