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Net Investment Income (Details) - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2023 | Mar. 31, 2022
Net Investment Income [Line Items] |  |
Gross investment income | $ 226,113 | $ 175,485
Investment expense | (2,715) | (1,973)
Net investment income | 223,398 | 173,512
Fixed maturity securities, including cash and cash equivalents and loans receivable |  |
Net Investment Income [Line Items] |  |
Gross investment income | 195,642 | 101,284
Arbitrage trading account |  |
Net Investment Income [Line Items] |  |
Gross investment income | 2,180 | 52,012
Equity securities |  |
Net Investment Income [Line Items] |  |
Gross investment income | 13,746 | 10,856
Investment funds |  |
Net Investment Income [Line Items] |  |
Gross investment income | 18,256 | 9,187
Real estate |  |
Net Investment Income [Line Items] |  |
Gross investment income | $ (3,711) | $ 2,146

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- Definition Amount, after investment expense, of income earned from investments in securities and real estate. Includes, but is not limited to, real estate investment, policy loans, dividends, and interest. Excludes realized gain (loss) on investments. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(2)) -URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263 + Details
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