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Net Investment Income (Details) - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2022 | Mar. 31, 2021
Net Investment Income [Line Items] |  |
Gross investment income | $ 175,485 | $ 160,027
Investment expense | (1,973) | (1,450)
Net investment income | 173,512 | 158,577
Fixed maturity securities, including cash and cash equivalents and loans receivable |  |
Net Investment Income [Line Items] |  |
Gross investment income | 101,284 | 94,677
Investment funds |  |
Net Investment Income [Line Items] |  |
Investment funds | 52,012 | 38,935
Arbitrage trading account |  |
Net Investment Income [Line Items] |  |
Gross investment income | 9,187 | 19,074
Equity securities |  |
Net Investment Income [Line Items] |  |
Gross investment income | 2,146 | 1,161
Real estate |  |
Net Investment Income [Line Items] |  |
Gross investment income | $ 10,856 | $ 6,180

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- Definition Amount before accretion (amortization) of purchase discount (premium) of interest income and dividend income on nonoperating securities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.7(a),(b)) -URI http://asc.fasb.org/extlink&oid=123367319&loc=SL114868664-224227 + Details
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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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