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Fair Value Measurements (Summarize Changes in Level 3 Assets) (Details) - USD ($) $ in Thousands | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2024 | Dec. 31, 2023
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Assets, beginning balance | $ 9,025 | $ 17,488
Assets, earnings | 718 | (927)
Assets, other comprehensive income | 0 | 0
Assets, Impairments | 0 | (7,601)
Assets, purchases | 0 | 0
Assets, (sales) | (223) | 0
Assets, maturities | 0 | 0
Assets. transfers out | 37 | 65
Assets, ending balance | 9,557 | 9,025
Equity securities |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Assets, beginning balance | 5,253 | 13,898
Assets, earnings | 741 | (1,044)
Assets, other comprehensive income | 0 | 0
Assets, Impairments | 0 | (7,601)
Assets, purchases | 0 | 0
Assets, (sales) | (185) | 0
Assets, maturities | 0 | 0
Assets. transfers out | 0 | 0
Assets, ending balance | 5,809 | 5,253
Common stock |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Assets, beginning balance | 1,558 | 2,599
Assets, earnings | 743 | (1,041)
Assets, other comprehensive income | 0 | 0
Assets, Impairments | 0 | 0
Assets, purchases | 0 | 0
Assets, (sales) | (128) | 0
Assets, maturities | 0 | 0
Assets. transfers out | 0 | 0
Assets, ending balance | 2,173 | 1,558
Preferred stocks |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Assets, beginning balance | 3,695 | 11,299
Assets, earnings | (2) | (3)
Assets, other comprehensive income | 0 | 0
Assets, Impairments | 0 | (7,601)
Assets, purchases | 0 | 0
Assets, (sales) | (57) | 0
Assets, maturities | 0 | 0
Assets. transfers out | 0 | 0
Assets, ending balance | 3,636 | 3,695
Arbitrage trading account |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Assets, beginning balance | 3,772 | 3,590
Assets, earnings | (23) | 117
Assets, other comprehensive income | 0 | 0
Assets, Impairments | 0 | 0
Assets, purchases | 0 | 0
Assets, (sales) | (38) | 0
Assets, maturities | 0 | 0
Assets. transfers out | 37 | 65
Assets, ending balance | $ 3,748 | $ 3,772

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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 gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-2 + Details
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- Definition Amount of gain (loss) recognized in other comprehensive income (OCI) from asset measured at fair value on recurring basis using unobservable input (level 3). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(1a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-2 + Details
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