Market Risk Benefits - Market Risk Benefits In Asset and Liability Positions (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022		Dec. 31, 2021	Jan. 01, 2021	Dec. 31, 2020
Liability for Future Policy Benefit, Activity [Line Items]
Market risk benefits assets	$ 2,367,243	$ 1,393,237	[1]
Market risk benefit liabilities	5,144,401	5,521,601	[1]
Variable Annuties
Liability for Future Policy Benefit, Activity [Line Items]
Net amount at risk	$ 9,041,651	$ 12,141,947		$ 2,566,157
Weighted-average attained age of contractholders	70 years	68 years		66 years
Market risk benefits assets	$ 2,367,243	$ 1,393,237		$ 1,786,565
Market risk benefit liabilities	5,144,401	5,521,601		9,764,443
Net liability		4,550,625		8,884,362	$ (12,032)	$ 13,577,543
Total, Net of Reinsurance
Liability for Future Policy Benefit, Activity [Line Items]
Net liability	$ 2,777,158	$ 4,128,364		$ 7,977,878		$ (12,032)

[1] Prior period amounts reflect the implementation of Accounting Standard Update ("ASU") 2018-12: Targeted Improvements to the Accounting for Long-Duration Contracts.