Investments - Recorded Investment in CMLs by LTV and DSC Ratio Categories (Details) - Commercial Mortgage - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Loan excluding loans under development	$ 2,407
Loans	$ 2,416	$ 2,174
% of Total	100.00%	100.00%
2022	$ 341
2021	1,300	$ 543
2020	488	0
2019	0	6
2018	0	0
Prior	278	324
Loans under development, amortized cost	9
Loans under development, fair value	9
Total Estimated Fair Value
Debt Securities, Available-for-sale [Line Items]
Loan excluding loans under development	$ 2,074
Loans		$ 2,265
% of Total	100.00%	100.00%
Greater than 1.25
Debt Securities, Available-for-sale [Line Items]
Loan excluding loans under development	$ 2,371
Loans		$ 2,132
2022	329
2021	1,300	543
2020	488	0
2019	0	4
2018	0	0
Prior	254	284
Greater than 1.00 but less than 1.25
Debt Securities, Available-for-sale [Line Items]
Loan excluding loans under development	7
Loans		33
2022	3
2021	0	0
2020	0	0
2019	0	2
2018	0	0
Prior	4	31
Greater than 1.00
Debt Securities, Available-for-sale [Line Items]
Loan excluding loans under development	29
Loans		9
Less than 1.00
Debt Securities, Available-for-sale [Line Items]
Loan excluding loans under development	29
Loans		9
2022	9
2021	0	0
2020	0	0
2019	0	0
2018	0	0
Prior	20	9
Less than 50.00%
Debt Securities, Available-for-sale [Line Items]
Loan excluding loans under development	$ 526
Loans		$ 668
% of Total	22.00%	31.00%
2022	$ 70
2021	120	$ 229
2020	207	0
2019	0	6
2018	0	0
Prior	129	313
Less than 50.00% \| Total Estimated Fair Value
Debt Securities, Available-for-sale [Line Items]
Loan excluding loans under development	$ 490
Loans		$ 745
% of Total	24.00%	33.00%
Less than 50.00% \| Greater than 1.25
Debt Securities, Available-for-sale [Line Items]
Loan excluding loans under development	$ 511
Loans		$ 626
Less than 50.00% \| Greater than 1.00 but less than 1.25
Debt Securities, Available-for-sale [Line Items]
Loan excluding loans under development	4
Loans		33
Less than 50.00% \| Greater than 1.00
Debt Securities, Available-for-sale [Line Items]
Loan excluding loans under development	11
Loans		9
50.00% to 59.99%
Debt Securities, Available-for-sale [Line Items]
Loan excluding loans under development	$ 706
Loans		$ 470
% of Total	29.00%	22.00%
2022	$ 149
2021	268	$ 192
2020	158	0
2019	0	0
2018	0	0
Prior	131	11
50.00% to 59.99% \| Total Estimated Fair Value
Debt Securities, Available-for-sale [Line Items]
Loan excluding loans under development	$ 615
Loans		$ 481
% of Total	30.00%	21.00%
50.00% to 59.99% \| Greater than 1.25
Debt Securities, Available-for-sale [Line Items]
Loan excluding loans under development	$ 706
Loans		$ 470
50.00% to 59.99% \| Greater than 1.00 but less than 1.25
Debt Securities, Available-for-sale [Line Items]
Loan excluding loans under development	0
Loans		0
50.00% to 59.99% \| Greater than 1.00
Debt Securities, Available-for-sale [Line Items]
Loan excluding loans under development	0
Loans		0
60.00% to 74.99%
Debt Securities, Available-for-sale [Line Items]
Loan excluding loans under development	$ 1,157
Loans		$ 1,036
% of Total	48.00%	47.00%
2022	$ 113
2021	912	$ 122
2020	123	0
2019	0	0
2018	0	0
Prior	9	0
60.00% to 74.99% \| Total Estimated Fair Value
Debt Securities, Available-for-sale [Line Items]
Loan excluding loans under development	$ 955
Loans		$ 1,039
% of Total	45.00%	46.00%
60.00% to 74.99% \| Greater than 1.25
Debt Securities, Available-for-sale [Line Items]
Loan excluding loans under development	$ 1,154
Loans		$ 1,036
60.00% to 74.99% \| Greater than 1.00 but less than 1.25
Debt Securities, Available-for-sale [Line Items]
Loan excluding loans under development	3
Loans		0
60.00% to 74.99% \| Greater than 1.00
Debt Securities, Available-for-sale [Line Items]
Loan excluding loans under development	0
Loans		$ 0
75.00% to 84.99%
Debt Securities, Available-for-sale [Line Items]
Loan excluding loans under development	$ 18
% of Total	1.00%
2022	$ 9
2021	0
2020	0
2019	0
2018	0
Prior	9
75.00% to 84.99% \| Total Estimated Fair Value
Debt Securities, Available-for-sale [Line Items]
Loan excluding loans under development	$ 14
% of Total	1.00%
75.00% to 84.99% \| Greater than 1.25
Debt Securities, Available-for-sale [Line Items]
Loan excluding loans under development	$ 0
75.00% to 84.99% \| Greater than 1.00 but less than 1.25
Debt Securities, Available-for-sale [Line Items]
Loan excluding loans under development	0
75.00% to 84.99% \| Greater than 1.00
Debt Securities, Available-for-sale [Line Items]
Loan excluding loans under development	$ 18

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Amortized cost excluding accrued interest, of financing receivable originated more than five years prior to current fiscal year. Excludes net investment in lease.

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