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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		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Schedule of Equity Method Investments [Line Items]
Net investment income earned	$ 63,889	$ 93,032	$ 206,713	$ 246,479
Other Investments	432,624		432,624		$ 409,032
Alternative Investments [Member]
Schedule of Equity Method Investments [Line Items]
Net investment income earned	(5,600)	42,800	22,800	92,900
Investments accounted for under the equity method [Member]
Schedule of Equity Method Investments [Line Items]
Net investment income	205,600	60,400	612,000	550,300
Realized gains	1,983,500	1,857,600	10,964,900	4,026,200
Net change in unrealized appreciation	(3,188,900)	11,188,200	(1,973,000)	20,767,900
Net income	$ (999,800)	$ 13,106,200	$ 9,603,900	$ 25,344,400

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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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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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