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Investments (Aggregated Income Statement Summarized Financial Information for Partnerhips in our Alternative Investment Portfolio) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Schedule of Equity Method Investments [Line Items]
Net investment income earned	$ 72,602	$ 69,716
Carrying Value	425,666		$ 409,032
Alternative Investments [Member]
Schedule of Equity Method Investments [Line Items]
Net investment income earned	19,100	20,200
Investments accounted for under the equity method [Member]
Schedule of Equity Method Investments [Line Items]
Net investment income	135,500	481,600
Realized gains	2,748,000	776,000
Net change in unrealized appreciation	5,178,200	4,630,800
Insurance Subsidiaries' alternative investments income	$ 8,061,700	$ 5,888,400

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The amount of net income (loss) reported by an equity method investment of the entity.

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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.

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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))
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Amount of investments classified as other.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
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