Market Risk Benefits - Market Risk Benefits In Asset and Liability Positions (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023	Dec. 31, 2022
Liability for Future Policy Benefit, Activity [Line Items]
Total market risk benefit assets	$ 2,550,164	$ 2,340,000	$ 2,367,243
Total market risk benefit liabilities	4,370,960	5,090,000	5,144,401
Variable Annuities
Liability for Future Policy Benefit, Activity [Line Items]
Net amount at risk	$ 8,732,024	$ 10,067,522
Weighted-average attained age of contractholders	71 years	69 years
Direct and assumed	$ 1,419,114	$ 1,165,762
Ceded	1,131,050	1,174,468
Total market risk benefit assets	2,550,164	2,340,230
Direct and assumed	4,085,018	4,862,177
Ceded	285,942	227,589
Total market risk benefit liabilities	4,370,960	5,089,766
Net liability	$ 1,820,796	$ 2,749,536	$ 3,694,950	$ 4,550,625