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Fair Values of Assets and Liabilities - Additional Information (Detail) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2021 | Jun. 30, 2020 | Jun. 30, 2021 | Jun. 30, 2020 | Dec. 31, 2020
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |
Available-for-sale Securities | $ 1,090,530 |  | $ 1,090,530 |  | $ 831,223
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3 | 0 | $ 0 | 0 | $ 0 |
Impaired loans considered to be credit risk of non-collection | 250 |  | 250 |  |
Updated appraisal requirement floor | 250 |  | 250 |  |
Other real estate owned | 394 |  | 394 |  | 1,215
Financial instrument of credit risk | 100 |  | 100 |  | $ 100
Fair Value, Assets Measured on Recurring Basis, Gain (Loss) Included in Other Income, Assets and Liabilities Continue to be held |  | 0 |  | 0 |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3 | 0 | 0 | 0 | 0 |
Total gains or losses included in earnings | 0 | 0 | 0 | 0 |
Derivatives mark to market | (277) | (221) | 1,153 | (1,962) |
Forward Contracts [Member] |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |
Derivatives mark to market |  |  | (800) |  |
Forward Contracts [Member] | Designated as Hedging Instrument [Member] |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |
Derivatives mark to market | 641 | (248) | (401) | 234 |
Other Assets [Member] |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3 | 0 | 0 | 0 | 0 |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3 | 0 | 0 | 0 | 0 |
Total gains or losses included in earnings | $ 0 | $ 0 | $ 0 | $ 0 |
Minimum [Member] |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |
Swap Rates Term Used to Determine Yield Curve |  |  | 3 years |  |
Maximum [Member] |  |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |  |
Swap Rates Term Used to Determine Yield Curve |  |  | 30 years |  |

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