Significant Accounting Policies - Schedule of Long-Duration Contracts (Details) - USD ($) $ in Thousands		Mar. 31, 2023	Dec. 31, 2022		Dec. 31, 2021
Liability for Future Policy Benefits for Payout Annuity With Life Contingency
Beginning balance, liability for future policy benefit		$ 317,418	$ 401,022
Liability for future policy benefit, adjustment		318,462	317,418		$ 401,022
Ending balance, liability for future policy benefit		318,462	317,418		401,022
Beginning balance, market risk benefit		2,225,621
Market risk benefit, after increase (decrease) from instrument-specific credit risk		2,422,881	2,225,621
Ending balance, market risk benefit		2,422,881	2,225,621
Deferred Policy Acquisition Costs
Beginning balance, deferred policy acquisition cost	[1]	2,773,643
Deferred policy acquisition costs		2,772,175	2,773,643	[1]
Ending balance, deferred policy acquisition cost		2,772,175	2,773,643	[1]
Deferred Sales Inducements
Beginning balance, deferred sale inducement cost	[1]	2,045,683
Deferred sales inducements		2,044,349	2,045,683	[1]
Ending balance, deferred sale inducement cost		$ 2,044,349	$ 2,045,683	[1]
Liability for Future Policy Benefits for Payout Annuity With Life Contingency
Liability for Future Policy Benefits for Payout Annuity With Life Contingency
Beginning balance, liability for future policy benefit					408,750
Liability for future policy benefit, adjustment
Market Risk Benefit Liability
Liability for Future Policy Benefits for Payout Annuity With Life Contingency
Beginning balance, market risk benefit					2,225,484
Market risk benefit, after increase (decrease) from instrument-specific credit risk
Ceded Market Risk Benefit (a)
Liability for Future Policy Benefits for Payout Annuity With Life Contingency
Beginning balance, market risk benefit					89,338
Market risk benefit, after increase (decrease) from instrument-specific credit risk
Fixed Index Annuities and Fixed Rate Annuities
Deferred Policy Acquisition Costs
Beginning balance, deferred policy acquisition cost					3,408,505
Deferred policy acquisition costs
Deferred Sales Inducements
Beginning balance, deferred sale inducement cost					2,216,685
Deferred sales inducements
As Reported | Liability for Future Policy Benefits for Payout Annuity With Life Contingency
Liability for Future Policy Benefits for Payout Annuity With Life Contingency
Beginning balance, liability for future policy benefit					337,467
Liability for future policy benefit, adjustment
As Reported | Market Risk Benefit Liability
Liability for Future Policy Benefits for Payout Annuity With Life Contingency
Beginning balance, market risk benefit					2,547,231
Market risk benefit, after increase (decrease) from instrument-specific credit risk
As Reported | Ceded Market Risk Benefit (a)
Liability for Future Policy Benefits for Payout Annuity With Life Contingency
Beginning balance, market risk benefit					62,108
Market risk benefit, after increase (decrease) from instrument-specific credit risk
As Reported | Fixed Index Annuities and Fixed Rate Annuities
Deferred Policy Acquisition Costs
Beginning balance, deferred policy acquisition cost					2,225,199
Deferred policy acquisition costs
Deferred Sales Inducements
Beginning balance, deferred sale inducement cost					1,448,375
Deferred sales inducements
Revision of Prior Period, Accounting Standards Update, Adjustment | Fixed Index Annuities and Fixed Rate Annuities
Deferred Policy Acquisition Costs
Beginning balance, deferred policy acquisition cost					1,183,306
Deferred policy acquisition costs
Deferred Sales Inducements
Beginning balance, deferred sale inducement cost					768,310
Deferred sales inducements
Adjustment to opening retained earnings for expected future policy benefits | Liability for Future Policy Benefits for Payout Annuity With Life Contingency
Liability for Future Policy Benefits for Payout Annuity With Life Contingency
Beginning balance, liability for future policy benefit					2,566
Liability for future policy benefit, adjustment
Adjustment for the effect of remeasurement of liability at current single A rate | Liability for Future Policy Benefits for Payout Annuity With Life Contingency
Liability for Future Policy Benefits for Payout Annuity With Life Contingency
Beginning balance, liability for future policy benefit					68,717
Liability for future policy benefit, adjustment
Adjustment for the removal of shadow adjustments | Market Risk Benefit Liability
Liability for Future Policy Benefits for Payout Annuity With Life Contingency
Beginning balance, market risk benefit					(584,636)
Market risk benefit, after increase (decrease) from instrument-specific credit risk
Adjustment for the cumulative effect of the changes in the instrument-specific credit risk between the original contract issuance date and the transition date | Market Risk Benefit Liability
Liability for Future Policy Benefits for Payout Annuity With Life Contingency
Beginning balance, market risk benefit					229,108
Market risk benefit, after increase (decrease) from instrument-specific credit risk
Adjustment for the remaining difference between previous carrying amount and fair value measurement for the MRB, exclusive of the instrument specific credit risk | Market Risk Benefit Liability
Liability for Future Policy Benefits for Payout Annuity With Life Contingency
Beginning balance, market risk benefit					33,781
Market risk benefit, after increase (decrease) from instrument-specific credit risk
Adjustment for the remaining difference between previous carrying amount and fair value measurement for the MRB, exclusive of the instrument specific credit risk | Ceded Market Risk Benefit (a)
Liability for Future Policy Benefits for Payout Annuity With Life Contingency
Beginning balance, market risk benefit					$ 27,230
Market risk benefit, after increase (decrease) from instrument-specific credit risk

[1] Certain prior period amounts have been recast. See Note 1 - Significant Accounting Policies for more information.