Net Investment Income (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Net Investment Income [Line Items]
Gross investment income	$ 144,430	$ 162,769	$ 409,187	$ 511,898
Investment expense	(1,780)	(1,077)	(6,343)	(3,619)
Net investment income	142,650	161,692	402,844	508,279
Fixed maturity securities, including cash and cash equivalents and loans receivable
Net Investment Income [Line Items]
Gross investment income	97,080	125,957	330,941	386,978
Investment funds
Net Investment Income [Line Items]
Gross investment income	18,235	19,033	1,260	77,284
Arbitrage trading account
Net Investment Income [Line Items]
Gross investment income	19,543	8,400	51,985	26,184
Real estate
Net Investment Income [Line Items]
Gross investment income	7,666	7,987	18,807	17,468
Equity securities
Net Investment Income [Line Items]
Gross investment income	$ 1,907	$ 1,392	$ 6,194	$ 3,984

Amount before accretion (amortization) of purchase discount (premium) of interest income and dividend income on nonoperating securities.

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Amount of expenses related to the generation of investment income.

+ 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 210.5-03.9)
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-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=116637232&loc=SL114874131-224263

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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=116637232&loc=SL114874131-224263

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+ References

No definition available.

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