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RESTRICTED STOCK - Summary of restricted stock (Details) - USD ($) $ in Thousands | Dec. 31, 2021 | Dec. 31, 2020
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Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items] |  |
Restricted stock | $ 37,732 | $ 60,707
FHLBNY |  |
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items] |  |
Restricted stock | 12,819 | $ 60,707
FRB capital stock |  |
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items] |  |
Restricted stock | 24,748 |
Bankers' Bank capital stock (ACBB) |  |
Federal Home Loan Bank, Advances, Branch of FHLB Bank [Line Items] |  |
Restricted stock | $ 165 |

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- Definition Investments which are not defined as or included in marketable (debt, equity, or other) securities whose use is restricted in whole or in part, generally by contractual agreements or regulatory requirements. For use in an unclassified balance sheet. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 954 -SubTopic 210 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=120413173&loc=SL6242262-115580 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 954 -SubTopic 210 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=120413209&loc=SL6242269-115581 + Details
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