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Allowance for Loan Credit Losses - Allowance and loans by impairment methodology (Details) $ in Millions | 9 Months Ended | 12 Months Ended
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Sep. 30, 2024 USD ($) loan | Dec. 31, 2023 loan
Allowance for Loan Credit Losses |  |
Number of collateral dependent loans | loan | 1 | 0
Individually evaluated for impairment, allowance | $ | $ 10.0 |

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- References No definition available. + Details
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- Definition Amount of allowance for credit loss on financing receivable evaluated on individual basis. Excludes financing receivable evaluated on collective basis. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 4 -Subparagraph (SAB Topic 6.L.5.a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480418/310-10-S99-4 Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 11B -Subparagraph (g) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481962/310-10-50-11B Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 30 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479391/326-20-30-2 + Details
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