Investments (excluding Consolidated Investment Entities) - Allowance for Credit Losses (Details) $ in Millions	6 Months Ended
	Jun. 30, 2020 USD ($)
Allowance for Loan and Lease Losses [Roll Forward]
Balance as of January 1	$ 0
Credit losses on securities for which credit losses were not previously recorded	17
Initial allowance for credit losses recognized on financial assets accounted for as PCD	0
Reductions for securities sold during the period	0
Reductions for intent to sell or more likely than not will be required to sell securities prior to recovery of amortized cost	0
Increase (decrease) on securities with allowance recorded in previous period	0
Write-offs	0
Recoveries of amounts previously written off	0
Balance as of June 30	17
Residential mortgage-backed securities
Allowance for Loan and Lease Losses [Roll Forward]
Balance as of January 1	0
Credit losses on securities for which credit losses were not previously recorded	2
Initial allowance for credit losses recognized on financial assets accounted for as PCD	0
Reductions for securities sold during the period	0
Reductions for intent to sell or more likely than not will be required to sell securities prior to recovery of amortized cost	0
Increase (decrease) on securities with allowance recorded in previous period	0
Write-offs	0
Recoveries of amounts previously written off	0
Balance as of June 30	2
Commercial mortgage-backed securities
Allowance for Loan and Lease Losses [Roll Forward]
Balance as of January 1	0
Credit losses on securities for which credit losses were not previously recorded	0
Initial allowance for credit losses recognized on financial assets accounted for as PCD	0
Reductions for securities sold during the period	0
Reductions for intent to sell or more likely than not will be required to sell securities prior to recovery of amortized cost	0
Increase (decrease) on securities with allowance recorded in previous period	0
Write-offs	0
Recoveries of amounts previously written off	0
Balance as of June 30	0
Foreign corporate private securities
Allowance for Loan and Lease Losses [Roll Forward]
Balance as of January 1	0
Credit losses on securities for which credit losses were not previously recorded	3
Initial allowance for credit losses recognized on financial assets accounted for as PCD	0
Reductions for securities sold during the period	0
Reductions for intent to sell or more likely than not will be required to sell securities prior to recovery of amortized cost	0
Increase (decrease) on securities with allowance recorded in previous period	0
Write-offs	0
Recoveries of amounts previously written off	0
Balance as of June 30	3
Other asset-backed securities
Allowance for Loan and Lease Losses [Roll Forward]
Balance as of January 1	0
Credit losses on securities for which credit losses were not previously recorded	12
Initial allowance for credit losses recognized on financial assets accounted for as PCD	0
Reductions for securities sold during the period	0
Reductions for intent to sell or more likely than not will be required to sell securities prior to recovery of amortized cost	0
Increase (decrease) on securities with allowance recorded in previous period	0
Write-offs	0
Recoveries of amounts previously written off	0
Balance as of June 30	$ 12