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Nature of Operations and Summary of Significant Accounting Policies - Allowance for Credit Losses and Loans Held for Sale (Details) - USD ($) $ in Thousands | Dec. 31, 2021 | Jan. 01, 2021 | Dec. 31, 2020
--- | --- | --- | ---
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |
Allowance for Credit Losses | $ 245 |  | $ 0
Loans | 9,241,861 |  | 9,243,174
PPP, CARES Act |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |
Loans | 106,600 |  | 667,100
State and municipal |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |
Allowance for Credit Losses | $ 245 |  | 0
Impact of adopting ASC 326 |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |
Loans |  | $ 4,776 |
Impact of adopting ASC 326 | State and municipal |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |
Allowance for Credit Losses |  | $ 245 | $ 245

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- Definition Amount, excluding accrued interest, of allowance for credit loss on investment in debt security measured at amortized cost (held-to-maturity). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446 + Details
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