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Investments - Schedule of Aggregated Income Statement Summarized Financial Information for Partnerships in our Alternative Investment Portfolio (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Schedule of Equity Method Investments [Line Items]
Net investment income earned	$ 120,691	$ 107,849
Investments Accounted For Under The Equity Method
Schedule of Equity Method Investments [Line Items]
Net investment income (loss)	400,700	(346,000)
Realized gains	612,000	1,830,800
Net change in unrealized appreciation (depreciation)	1,879,400	3,819,000
Net income	2,892,100	5,303,800
Alternative investments
Schedule of Equity Method Investments [Line Items]
Net investment income earned	$ 7,079	$ 6,881

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