Investments - Portion of Net Unrealized Gains and Losses Recognized During Reporting Period (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Equity securities:
Net (losses) gains recognized during the period	$ (13,238)	$ (186)	$ 5,056
Less: net losses recognized on securities sold	(1,866)	(76)	(469)
Net unrealized (losses) gains recognized on securities held at reporting date	$ (11,372)	$ (110)	$ 5,525