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SECURITIES (Narrative) (Details) | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2021 USD ($) security | Dec. 31, 2020 USD ($) security
Schedule of Investments [Line Items] |  |
Available for sale securities past due or non-accrual | $ 0 | $ 0
Available for sale securities that had been in a continuous loss position for more than 12 months | 96,800,000 | 17,600,000
Available-for-sale securities, continuous unrealized loss position, 12 months or longer, accumulated loss | 1,790,000 | 101,000
AFS securities in an unrealized loss, credit related impairment | 0 | 0
HTM securities past due or non accrual | $ 0 | $ 0
Federal Home Loan Bank requires Bank to maintain percentage of stock equal to outstanding borrowings | 3.75% | 4.25%
Percentage of Federal Reserve Bank of Richmond reserve | 6.00% | 6.00%
Restricted equity securities consist of Federal Reserve Bank stock | $ 67,000,000.0 | $ 67,000,000.0
Federal Home Loan Bank Stock | $ 9,800,000 | $ 27,800,000
Available-for-sale Securities |  |
Schedule of Investments [Line Items] |  |
Available for sale securities that had been in a continuous loss position for more than 12 months, Number of issues | security | 26 | 15
Non-agency collateralized mortgage obligations |  |
Schedule of Investments [Line Items] |  |
SSFA rating percentage | 20.00% |

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- Definition Federal home loan bank requires bank to maintain percentage of stock equal to outstanding borrowings. + References No definition available. + Details
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- Definition Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without allowance for credit loss. Includes beneficial interest in securitized financial asset. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27337-111563 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=124269663&loc=SL82922890-210455 + Details
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