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Securities Held-To-Maturity - Rollforward of Allowance (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2023 | Sep. 30, 2023
Changes in the allowance for credit losses |  |
Allowance for credit loss, Beginning balance | $ 4,534 | $ 3,153
Provision for credit loss expense/(reversal) | 1,409 | 2,790
Allowance for credit loss, Ending balance | 5,943 | 5,943
APL certificates |  |
Changes in the allowance for credit losses |  |
Allowance for credit loss, Beginning balance | 3,375 | 2,783
Provision for credit loss expense/(reversal) | (1,035) | (443)
Allowance for credit loss, Ending balance | 2,340 | 2,340
B Piece bonds |  |
Changes in the allowance for credit losses |  |
Allowance for credit loss, Beginning balance | 1,159 | 370
Provision for credit loss expense/(reversal) | 2,444 | 3,233
Allowance for credit loss, Ending balance | $ 3,603 | $ 3,603

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- Definition Amount of allowance for credit loss for debt security measured at amortized cost (held-to-maturity). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (aaa) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481800/320-10-50-5 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479344/326-20-45-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479319/326-20-50-13 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479319/326-20-50-13 + Details
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
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- Definition Amount of expense (reversal of expense) for expected credit loss on investment in debt security measured at amortized cost (held-to-maturity). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479319/326-20-50-13 + Details
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