Investments - Gains (Losses) Related to Equity Securities (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Investments, Debt and Equity Securities [Abstract]
Net (losses) gains recognized during the period	$ (4,991)	$ 2,603	$ 3,456	$ (31,275)
Less: net gains recognized during the period on equity securities sold during the period	754	8,197	6,603	17,953
Unrealized (losses) recognized during the period on equity securities held	$ (5,745)	$ (5,594)	$ (3,147)	$ (49,228)