Business and Basis of Presentation (Additional Insurance Reserves) (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Jun. 30, 2022	Jan. 01, 2021	Dec. 31, 2020
Liability for Future Policy Benefit, Activity [Line Items]
Balance	$ 18,190,646	$ 19,163,296
Additional insurance reserves
Liability for Future Policy Benefit, Activity [Line Items]
Balance			$ 10,878,087
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Balance prior to transition, excluding amounts related to unrealized investment gains and losses			9,708,115
Balance after transition, excluding amounts related to unrealized investment gains and losses			9,708,115
Amounts related to unrealized investment gains and losses after transition			1,169,972
Reinsurance recoverable			10,685,150
Balance after reinsurance recoverable, end of period, post-flooring			192,937
Additional insurance reserves | As Previously Reported
Liability for Future Policy Benefit, Activity [Line Items]
Balance				$ 9,951,896
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Balance prior to transition, excluding amounts related to unrealized investment gains and losses			8,471,196
Balance after transition, excluding amounts related to unrealized investment gains and losses			8,471,196
Additional insurance reserves | Unwinding amounts related to unrealized investment gains and losses
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Cash flow change			(1,480,700)
Additional insurance reserves | Reclassification of future policy benefits additional insurance reserves to market risk benefits
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Cash flow change			(534,422)
Additional insurance reserves | Updates to certain universal life contract liabilities
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Cash flow change			1,771,341
Additional insurance reserves | Variable/Universal Life
Liability for Future Policy Benefit, Activity [Line Items]
Balance			10,878,087
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Balance prior to transition, excluding amounts related to unrealized investment gains and losses			9,708,115
Balance after transition, excluding amounts related to unrealized investment gains and losses			9,708,115
Amounts related to unrealized investment gains and losses after transition			1,169,972
Reinsurance recoverable			10,685,150
Balance after reinsurance recoverable, end of period, post-flooring			192,937
Additional insurance reserves | Variable/Universal Life | As Previously Reported
Liability for Future Policy Benefit, Activity [Line Items]
Balance				9,363,585
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Balance prior to transition, excluding amounts related to unrealized investment gains and losses			7,936,774
Balance after transition, excluding amounts related to unrealized investment gains and losses			7,936,774
Additional insurance reserves | Variable/Universal Life | Unwinding amounts related to unrealized investment gains and losses
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Cash flow change			(1,426,811)
Additional insurance reserves | Variable/Universal Life | Reclassification of future policy benefits additional insurance reserves to market risk benefits
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Cash flow change			0
Additional insurance reserves | Variable/Universal Life | Updates to certain universal life contract liabilities
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Cash flow change			1,771,341
Additional insurance reserves | Variable Annuities
Liability for Future Policy Benefit, Activity [Line Items]
Balance			0
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Balance prior to transition, excluding amounts related to unrealized investment gains and losses			0
Balance after transition, excluding amounts related to unrealized investment gains and losses			0
Amounts related to unrealized investment gains and losses after transition			0
Reinsurance recoverable			0
Balance after reinsurance recoverable, end of period, post-flooring			0
Additional insurance reserves | Variable Annuities | As Previously Reported
Liability for Future Policy Benefit, Activity [Line Items]
Balance				$ 588,311
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Balance prior to transition, excluding amounts related to unrealized investment gains and losses			534,422
Balance after transition, excluding amounts related to unrealized investment gains and losses			534,422
Additional insurance reserves | Variable Annuities | Unwinding amounts related to unrealized investment gains and losses
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Cash flow change			(53,889)
Additional insurance reserves | Variable Annuities | Reclassification of future policy benefits additional insurance reserves to market risk benefits
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Cash flow change			(534,422)
Additional insurance reserves | Variable Annuities | Updates to certain universal life contract liabilities
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Cash flow change			$ 0