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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		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Schedule of Equity Method Investments [Line Items]
Net investment income earned	$ 70,222	$ 83,731	$ 142,824	$ 153,447
Other Investments	429,546		429,546		$ 409,032
Alternative Investments [Member]
Schedule of Equity Method Investments [Line Items]
Net investment income earned	9,300	29,900	28,400	50,100
Investments accounted for under the equity method [Member]
Schedule of Equity Method Investments [Line Items]
Net investment income	270,900	8,400	406,500	490,000
Realized gains	6,233,500	1,392,500	8,981,500	2,168,600
Net change in unrealized appreciation	(3,962,400)	4,948,900	1,215,900	9,579,700
Net income	$ 2,542,000	$ 6,349,800	$ 10,603,900	$ 12,238,300

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

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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
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