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Description of Business and Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Jan. 01, 2019
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Days from origination after which mortgage loan are sold | 30 days |  |  |
Loan upon which a default of principal or interest has existed for a period | 90 days |  |  |
Intangible assets, Estimated useful lives | 7 years 7 months 6 days |  |  |
Advertising costs | $ 3,800 | $ 3,500 | $ 3,400 |
Revenue recognition, description of performance obligation | the Company offers various services to customers that generate revenue. Contract performance typically occurs in one year or less. |  |  |
Incremental cost of obtaining contract | true |  |  |
Revenue recognition, description of payment terms | Revenue is recognized when the transactions occur or as services are performed over primarily monthly or quarterly periods. Payment is typically received in the period the transactions occur, or in some cases, within 90 days of the service period. |  |  |
Right-of-use lease assets | $ 5,700 |  |  | $ 4,300
Lease liabilities | $ 5,620 |  |  | $ 4,300
Core Deposit Intangibles [Member] |  |  |  |
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Intangible assets, Estimated useful lives | 7 years 9 months 18 days |  |  |
Minimum [Member] | ASU No. 2016-13 [Member] |  |  |  |
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Expected percentage of decrease in allowance for loan loss | 0.00% |  |  |
Minimum [Member] | Core Deposit Intangibles [Member] |  |  |  |
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Intangible assets, Estimated useful lives | 7 years |  |  |
Minimum [Member] | Customer Relationship Intangibles [Member] |  |  |  |
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Intangible assets, Estimated useful lives | 3 years |  |  |
Maximum [Member] | ASU No. 2016-13 [Member] |  |  |  |
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Expected percentage of decrease in allowance for loan loss | 5.00% |  |  |
Maximum [Member] | Core Deposit Intangibles [Member] |  |  |  |
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Intangible assets, Estimated useful lives | 10 years |  |  |
Maximum [Member] | Customer Relationship Intangibles [Member] |  |  |  |
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Intangible assets, Estimated useful lives | 18 years |  |  |
Home Equity Lines of Credit [Member] | Maximum [Member] |  |  |  |
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Loans and finance receivables portfolio percentage | 9.00% |  |  |
First Liens [Member] | Minimum [Member] |  |  |  |
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Loans and finance receivables portfolio percentage | 83.00% |  |  |
Junior Liens [Member] | Maximum [Member] |  |  |  |
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items] |  |  |  |
Loans and finance receivables portfolio percentage | 8.00% |  |  |

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