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Investments - Selected Balance Sheet Information and Selected Statement of Operations Information for SLP III and SLP IV (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Investment Company, Nonconsolidated Subsidiary [Line Items]
Interest and dividend receivable	$ 44,169		$ 44,169		$ 42,379
SLP III
Investment Company, Nonconsolidated Subsidiary [Line Items]
Dividend income	5,600	$ 5,567	17,000	$ 17,205
Interest and dividend receivable	5,600		5,600		6,100
SLP IV
Investment Company, Nonconsolidated Subsidiary [Line Items]
Dividend income	3,794	$ 3,794	11,521	$ 12,153
Interest and dividend receivable	$ 3,794		$ 3,794		$ 4,075

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Amount of dividend and interest receivable from investment.

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