Investments (Narrative) (Details) $ in Millions	3 Months Ended	6 Months Ended	12 Months Ended
	Jun. 30, 2023 USD ($) loan item	Jun. 30, 2023 USD ($) loan item	Dec. 31, 2022 USD ($) loan item
Schedule of Investments [Line Items]
Decrease in gross AFS securities unrealized gains (losses)		$ (3,800)
Number of partnerships in alternative investment portfolio | item	329	329	328
Alternative investments as a percentage of overall invested assets		2.00%	2.00%
Fair value of collateral received that we are permitted to sell or re-pledge	$ 25	$ 25
Investment commitments	2,500	2,500
Investment commitments for limited partnerships	1,900	1,900
Investment commitments for private placements	226	226
Investment commitments for mortgage loans on real estate	$ 412	$ 412
Minimum [Member]
Schedule of Investments [Line Items]
Percentage of the fair value of securities obtained as collateral under reverse repurchase agreements.	80.00%	80.00%
Maximum [Member]
Schedule of Investments [Line Items]
Percentage of the fair value of securities obtained as collateral under reverse repurchase agreements.	95.00%	95.00%
Loan modifications	$ 1	$ 1
Mortgage Loans On Real Estate [Member] | Commercial [Member] | Maximum [Member]
Schedule of Investments [Line Items]
Impaired financing receivable, principal balance	$ 1	$ 1
Mortgage Loans On Real Estate [Member] | Residential [Member]
Schedule of Investments [Line Items]
Number of loans past due | loan	90	90	73
Financing Receivable, Number of Loans In Foreclosure | loan	67	67	49
Financing Receivable, 90 Days or More Past Due, Still Accruing	$ 28	$ 28	$ 21
Number of impaired loans | loan	64	64	37
Impaired financing receivable, principal balance	$ 29	$ 29	$ 16
Geographic Concentration Risk [Member] | Mortgage Loans On Real Estate [Member] | Commercial [Member] | California [Member]
Schedule of Investments [Line Items]
Concentration risk, percentage		28.00%	28.00%
Geographic Concentration Risk [Member] | Mortgage Loans On Real Estate [Member] | Commercial [Member] | Texas [Member]
Schedule of Investments [Line Items]
Concentration risk, percentage		9.00%	9.00%
Geographic Concentration Risk [Member] | Mortgage Loans On Real Estate [Member] | Residential [Member] | California [Member]
Schedule of Investments [Line Items]
Concentration risk, percentage		15.00%	17.00%
Geographic Concentration Risk [Member] | Mortgage Loans On Real Estate [Member] | Residential [Member] | NEW JERSEY
Schedule of Investments [Line Items]
Concentration risk, percentage			12.00%
Geographic Concentration Risk [Member] | Mortgage Loans On Real Estate [Member] | Residential [Member] | NEW YORK
Schedule of Investments [Line Items]
Concentration risk, percentage		13.00%
Corporate Bonds [Member]
Schedule of Investments [Line Items]
Percentage of fair value rated as investment grade	96.00%	96.00%	96.00%
Amortized cost of portfolio rated below investment grade	$ 3,100	$ 3,100	$ 3,500
Fair value of portfolio rated below investment grade	2,900	2,900	3,300
Securities Investment [Member] | White Chapel LLC [Member] | Investments [Member]
Schedule of Investments [Line Items]
Fair value	1,000	$ 1,000	$ 1,000
Concentration risk, percentage		1.00%	1.00%
Securities Investment [Member] | Financial Service [Member] | Investments [Member]
Schedule of Investments [Line Items]
Fair value	20,000	$ 20,000	$ 19,200
Concentration risk, percentage		15.00%	15.00%
Securities Investment [Member] | Consumer Non-Cyclical Industry [Member] | Investments [Member]
Schedule of Investments [Line Items]
Fair value	$ 15,100	$ 15,100	$ 14,300
Concentration risk, percentage		11.00%	11.00%
Securities Investment [Member] | Federal Home Loan Mortgage Corporation [Member] | Investments [Member]
Schedule of Investments [Line Items]
Fair value			$ 702
Concentration risk, percentage			1.00%