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INVESTMENT AND MORTGAGE-BACKED SECURITIES - Sales Information and Marketable Equity Securities (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Sales of Available-for-sale Securities: |  |  |
Proceeds | $ 138,077 | $ 94,252 | $ 148,857
Gross gains | 1,327 | 4,592 | 551
Tax expense on gain | 421 | 1,444 | 175
Gross losses | 120 |  | 520
Tax benefit on loss | 38 |  | 166
Proceeds: |  |  |
Marketable equity securities | 6,101 | 546 | 570
Net gain on equity securities | 131 | 361 | 531
Securities transferred to held-to-maturity | 140,399 |  |
Sales of securities held-to-maturity | 0 | 0 | 0
Transfers to or from securities held-to-maturity | $ 0 | $ 0 | $ 0

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- Definition Amount of realized gain 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 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27357-111563 + Details
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- Definition Amount of realized 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 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27357-111563 + Details
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