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MARKETABLE SECURITIES - Narrative (Details) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2021 USD ($) Position security | Dec. 31, 2020 USD ($)
Investments Debt And Equity Securities [Abstract] |  |
Allowance for credit losses for available for sale debt securities | $ 0 |
Other than temporary impairment losses on debt securities related to credit losses |  | $ 0
Number of investment in an unrealized loss position | Position | 16 |
Percentage of unrealized loss exceeds book value | 20.00% |
Number of securities other than agencies amount | security | 0 |
Fair value of securities pledged as collateral | $ 317,293,000 | $ 314,962,000
Number of securities sold | security | 0 |

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- Definition Amount of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121582814&loc=SL82922900-210455 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 50 -Paragraph 9 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=121582814&loc=SL82922900-210455 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (aaa) -URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27161-111563 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121558606&loc=SL82898722-210454 + Details
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