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v3.20.4

Summary of Significant Accounting Policies (Details) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 USD ($) Loan | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($)
Loans [Abstract] |  |  |
Minimum number of days past due for loans to be considered nonperforming | 90 days |  |
Period of sustained repayment performance for nonperforming TDRs to be returned to performing status | 6 months |  |
Other Financial Instruments [Abstract] |  |  |
Standby letters of credit expiration period | 1 year |  |
Noninterest Income [Abstract] |  |  |
Total noninterest income in-scope of ASC 606 | $ 140,921 | $ 134,455 | $ 126,012
Total noninterest income out-of-scope of ASC 606 | 5,355 | 9,568 | (1,250)
Total noninterest income | $ 146,276 | 144,023 | 124,762
Minimum [Member] |  |  |
Allowance for Credit Losses [Abstract] |  |  |
Threshold period past due for loans to be written off | 90 days |  |
Maximum [Member] |  |  |
Allowance for Credit Losses [Abstract] |  |  |
Threshold period past due for loans to be written off | 120 days |  |
Paycheck Protection Program [Member] |  |  |
Allowance for Credit Losses [Abstract] |  |  |
Number of loans processed | Loan | 3,000 |  |
Paycheck Protection Program [Member] | Minimum [Member] |  |  |
Allowance for Credit Losses [Abstract] |  |  |
Amount of loans processed | $ 548,000 |  |
COVID-19 [Member] |  |  |
Loans [Abstract] |  |  |
Loans in modification programs related to COVID-19 | 110,800 |  |
Service Charges on Deposit Accounts [Member] |  |  |
Noninterest Income [Abstract] |  |  |
Total noninterest income in-scope of ASC 606 | 13,201 | 17,151 | 17,224
ATM and Debit Card Fees [Member] |  |  |
Noninterest Income [Abstract] |  |  |
Total noninterest income in-scope of ASC 606 | 25,960 | 23,893 | 22,699
Retirement Plan Administration Fees [Member] |  |  |
Noninterest Income [Abstract] |  |  |
Total noninterest income in-scope of ASC 606 | 35,851 | 30,388 | 26,992
Wealth Management [Member] |  |  |
Noninterest Income [Abstract] |  |  |
Total noninterest income in-scope of ASC 606 | 29,247 | 28,400 | 28,747
Insurance [Member] |  |  |
Noninterest Income [Abstract] |  |  |
Total noninterest income in-scope of ASC 606 | 14,757 | 15,770 | 15,122
Other [Member] |  |  |
Noninterest Income [Abstract] |  |  |
Total noninterest income in-scope of ASC 606 | $ 21,905 | $ 18,853 | $ 15,228
Commercial Loans [Member] | Commercial Real Estate [Member] | Maximum [Member] |  |  |
Allowance for Credit Losses [Abstract] |  |  |
Loan amount, percentage of appraised value or purchase price of the property | 80.00% |  |
Consumer Loans [Member] | Auto [Member] | Minimum [Member] |  |  |
Allowance for Credit Losses [Abstract] |  |  |
Principal repayment term of loan | 3 years |  |
Consumer Loans [Member] | Auto [Member] | Maximum [Member] |  |  |
Allowance for Credit Losses [Abstract] |  |  |
Principal repayment term of loan | 6 years |  |
Consumer Loans [Member] | Installment Loans [Member] | Minimum [Member] |  |  |
Allowance for Credit Losses [Abstract] |  |  |
Principal repayment term of loan | 1 year |  |
Consumer Loans [Member] | Installment Loans [Member] | Maximum [Member] |  |  |
Allowance for Credit Losses [Abstract] |  |  |
Principal repayment term of loan | 15 years |  |
Residential [Member] | Maximum [Member] |  |  |
Allowance for Credit Losses [Abstract] |  |  |
Loan amount, percentage of appraised value or purchase price of the property | 85.00% |  |
Residential [Member] | Home Equity [Member] | Maximum [Member] |  |  |
Allowance for Credit Losses [Abstract] |  |  |
Loan amount, percentage of equity in property | 85.00% |  |
Term of draw | 10 years |  |
Term of amortization | 15 years |  |

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- Definition The threshold period past due for a loan to be considered nonperforming, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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