Statutory Information - Statutory financial information of insurance subsidiaries (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Statutory Capital [Abstract]
Statutory net income	$ 440,944	$ 295,811	$ 65,201
Statutory policyholders' surplus	924,977	1,220,714	1,339,509
Contingency reserve	$ 4,669,724	$ 4,126,604	$ 3,585,864