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Fair Value of Financial Instruments (Carrying Amounts and Estimated Fair Values of Financial Instruments) (Details) - USD ($) $ in Thousands | Mar. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Assets: |  |
Equity securities | $ 1,279,955 | $ 1,185,894
Arbitrage trading account | 609,000 | 944,000
Loans receivable | 187,455 | 187,981
Carrying Value |  |
Assets: |  |
Fixed maturity securities | 18,091,113 | 17,587,349
Equity securities | 1,279,955 | 1,185,894
Arbitrage trading account | 609,001 | 944,230
Loans receivable | 194,944 | 193,002
Cash and cash equivalents | 1,242,357 | 1,449,346
Trading account receivables from brokers and clearing organizations | 583,970 | 233,863
Due from broker | 17,207 | 3,609
Liabilities: |  |
Senior notes and other debt | 1,827,981 | 1,828,823
Subordinated debentures | 1,008,551 | 1,008,371
Fair Value |  |
Assets: |  |
Fixed maturity securities | 18,095,068 | 17,591,626
Equity securities | 1,279,955 | 1,185,894
Arbitrage trading account | 609,001 | 944,230
Loans receivable | 187,455 | 187,981
Cash and cash equivalents | 1,242,357 | 1,449,346
Trading account receivables from brokers and clearing organizations | 583,970 | 233,863
Due from broker | 17,207 | 3,609
Liabilities: |  |
Senior notes and other debt | 1,501,671 | 1,439,188
Subordinated debentures | $ 836,796 | $ 805,600

X
- Definition Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. + References No definition available. + Details
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- Definition Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 45 -Paragraph 1A -URI http://asc.fasb.org/extlink&oid=123594786&loc=SL75136599-209740 + Details
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- Definition Fair value of subordinated debt obligations including, but not limited to, subordinated loan, subordinated bond, subordinated debenture or junior debt. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258 + Details
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- Definition Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -URI http://asc.fasb.org/subtopic&trid=2196772 + Details
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- Definition The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. + References No definition available. + Details
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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.4) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 + Details
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- Definition Due From Brokers, Fair Value Disclosure + References No definition available. + Details
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