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Loans and Allowance for loan losses (Narrative) (Details) | 12 Months Ended
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Dec. 31, 2021 USD ($) loan | Dec. 31, 2020 USD ($) loan | Dec. 31, 2019 loan
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Amount of loan | $ 1,440,000 | $ 1,571,000 |
Number of loans default | loan | 3 | 3 |
Number of new loans default | 0 | 0 |
Balance of capitalized servicing rights | $ 2,633,000 | $ 2,390,000 |
Aggregate balances of loans serviced to participants | 3,962,000 | 4,291,000 |
Aggregate balances of loans serviced to third party | 314,953,000 | 300,700,000 |
Loans and Leases Receivable, Impaired, Commitment to Lend | 0 | 0 |
Amount of consumer mortgages and loans secured by residential real estate properties in process of foreclosure | 935,000 | 636,000 |
Mortgage Servicing Rights (MSR) Impairment (Recovery) | 0 | 0 |
Residential mortgage |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Number of loans default | loan |  |  | 2
Home equity |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Number of loans default | loan |  |  | 1
Residential |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Unpaid principal balances of loans held for sale | $ 3,950,000 | $ 2,718,000 |

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- Definition The undiscounted sum of all amounts, including amounts deemed principal, interest, fees, penalties, and other under the loan, owed to the investor at the reporting date, whether or not currently due and whether or not any such amounts have been written or charged off by the investor. This relates to loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 15 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=123409700&loc=d3e13503-111538 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=121614798&loc=d3e15032-111544 + Details
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- Definition Principal amount of transferred financial assets in which the transferor has continuing involvement with the assets underlying the transaction. Continuing involvement includes, but is not limited to, servicing, recourse, and restrictions on transferor's interests in transferred financial assets. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=121570589&loc=d3e107314-111719 + Details
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- Definition The adjustment to the carrying value of the rights retained or purchased to service mortgages. These adjustments are made when the estimate of the fair value is changed. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 50 -Section 50 -Paragraph 4 -Subparagraph (a)(6) -URI http://asc.fasb.org/extlink&oid=125521744&loc=d3e122739-111746 + Details
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