Financing Receivables - Credit Quality Information - Syndicated Loans (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Dec. 31, 2022
Financing receivables - credit quality information
Loan write-offs	$ 1
Commercial Loans
Financing receivables - credit quality information
Loan write-offs	1
Commercial Loans | Syndicated loans
Financing receivables - credit quality information
Loan write-offs	0
Amortized cost basis by year of origination and loan-to-value ratio
Year 1	1	$ 15
Year 2	14	39
Year 3	38	12
Year 4	12	26
Year 5	25	23
Prior	75	60
Total amortized cost basis	165	175
Commercial Loans | Syndicated loans | Risk 5
Amortized cost basis by year of origination and loan-to-value ratio
Year 1	0	1
Year 2	1	0
Year 3	0	0
Year 4	0	0
Year 5	0	0
Prior	2	0
Total amortized cost basis	3	1
Commercial Loans | Syndicated loans | Risk 4
Amortized cost basis by year of origination and loan-to-value ratio
Year 1	0	0
Year 2	0	0
Year 3	0	0
Year 4	1	2
Year 5	2	0
Prior	0	2
Total amortized cost basis	3	4
Commercial Loans | Syndicated loans | Risk 3
Amortized cost basis by year of origination and loan-to-value ratio
Year 1	0	0
Year 2	0	9
Year 3	8	1
Year 4	1	6
Year 5	3	5
Prior	12	8
Total amortized cost basis	24	29
Commercial Loans | Syndicated loans | Risk 2
Amortized cost basis by year of origination and loan-to-value ratio
Year 1	0	8
Year 2	9	21
Year 3	21	7
Year 4	6	12
Year 5	11	5
Prior	27	28
Total amortized cost basis	74	81
Commercial Loans | Syndicated loans | Risk 1
Amortized cost basis by year of origination and loan-to-value ratio
Year 1	1	6
Year 2	4	9
Year 3	9	4
Year 4	4	6
Year 5	9	13
Prior	34	22
Total amortized cost basis	61	60
Commercial Loans | Syndicated loans | Past due
Amortized cost basis by year of origination and loan-to-value ratio
Total amortized cost basis	$ 0	$ 0