Adoption of ASU 2018-12 - Summary of Changes in Net Liability Position of MRBs (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
MRBs, Net	$ (2,178)	$ (729)		$ 5,334
Retirement Plan Services
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
MRBs, Net				9
Accounting Standards Update 2018-12 | Cumulative Effect to Retained Earnings | Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
MRBs, Net				7,956
Accounting Standards Update 2018-12 | Cumulative Effect to Retained Earnings | Retained Earnings | Retirement Plan Services
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
MRBs, Net				10
As Previously Reported
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
MRBs, Net				1,034
As Previously Reported | Retirement Plan Services
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
MRBs, Net				11
Cumulative Effect of Credit Risk to AOCI | Accounting Standards Update 2018-12 | Cumulative Effect to Retained Earnings | Accumulated Other Comprehensive Income (Loss)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
MRBs, Net				(3,656)
Cumulative Effect of Credit Risk to AOCI | Accounting Standards Update 2018-12 | Cumulative Effect to Retained Earnings | Accumulated Other Comprehensive Income (Loss) | Retirement Plan Services
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
MRBs, Net				(12)
Variable Annuities
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
MRBs, Net	(2,180)	(662)	$ 2,398	5,207
Variable Annuities | Cumulative Effect to Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
MRBs, Net		(2,173)	(2,425)
Variable Annuities | Accounting Standards Update 2018-12 | Cumulative Effect to Retained Earnings | Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
MRBs, Net				7,968
Variable Annuities | As Previously Reported
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
MRBs, Net				831
Variable Annuities | Cumulative Effect of Credit Risk to AOCI | Accounting Standards Update 2018-12 | Cumulative Effect to Retained Earnings | Accumulated Other Comprehensive Income (Loss)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
MRBs, Net				(3,592)
Fixed Annuities
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
MRBs, Net	$ 32	(45)	114	118
Fixed Annuities | Cumulative Effect to Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
MRBs, Net		$ (40)	$ (44)
Fixed Annuities | Accounting Standards Update 2018-12 | Cumulative Effect to Retained Earnings | Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
MRBs, Net				(22)
Fixed Annuities | As Previously Reported
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
MRBs, Net				192
Fixed Annuities | Cumulative Effect of Credit Risk to AOCI | Accounting Standards Update 2018-12 | Cumulative Effect to Retained Earnings | Accumulated Other Comprehensive Income (Loss)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
MRBs, Net				$ (52)