Investments - Loans by Debt Service Coverage Ratio (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2022	Dec. 31, 2021
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	$ 4,175	$ 4,233
Loans and Leases Receivable, Debt Service Coverage, Benchmark Ratio	100.00%
Greater than 1.5x
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Loans Receivable, Debt Service Coverage Ratio, Minimum	150.00%	150.00%
Commercial mortgage loans	$ 3,017	$ 3,060
1.25x - 1.5x
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Loans Receivable, Debt Service Coverage Ratio, Minimum	125.00%	125.00%
Loans Receivable, Debt Service Coverage Ratio, Maximum	150.00%	150.00%
Commercial mortgage loans	$ 388	$ 377
1.0x - 1.25x
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Loans Receivable, Debt Service Coverage Ratio, Minimum	100.00%	100.00%
Loans Receivable, Debt Service Coverage Ratio, Maximum	125.00%	125.00%
Commercial mortgage loans	$ 441	$ 449
Less than 1.0x
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Loans Receivable, Debt Service Coverage Ratio, Maximum	100.00%	100.00%
Commercial mortgage loans	$ 329	$ 347
Commercial mortgage loans secured by land or construction loans
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	0	0
Year of Origination 2020
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	356	385
Year of Origination 2020 | Greater than 1.5x
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	313	342
Year of Origination 2020 | 1.25x - 1.5x
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	14	15
Year of Origination 2020 | 1.0x - 1.25x
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	23	23
Year of Origination 2020 | Less than 1.0x
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	6	5
Year of Origination 2020 | Commercial mortgage loans secured by land or construction loans
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	0	0
Year of Origination 2019
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	339	356
Year of Origination 2019 | Greater than 1.5x
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	201	206
Year of Origination 2019 | 1.25x - 1.5x
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	37	43
Year of Origination 2019 | 1.0x - 1.25x
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	83	84
Year of Origination 2019 | Less than 1.0x
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	18	23
Year of Origination 2019 | Commercial mortgage loans secured by land or construction loans
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	0	0
Year of Origination 2018
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	168	173
Year of Origination 2018 | Greater than 1.5x
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	96	96
Year of Origination 2018 | 1.25x - 1.5x
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	3	3
Year of Origination 2018 | 1.0x - 1.25x
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	48	49
Year of Origination 2018 | Less than 1.0x
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	21	25
Year of Origination 2018 | Commercial mortgage loans secured by land or construction loans
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	0	0
Year of Origination 2017
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	741	748
Year of Origination 2017 | Greater than 1.5x
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	353	355
Year of Origination 2017 | 1.25x - 1.5x
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	138	139
Year of Origination 2017 | 1.0x - 1.25x
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	92	93
Year of Origination 2017 | Less than 1.0x
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	158	161
Year of Origination 2017 | Commercial mortgage loans secured by land or construction loans
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	0	0
Year of Origination 2016
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	1,825	1,901
Year of Origination 2016 | Greater than 1.5x
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	1,419	1,505
Year of Origination 2016 | 1.25x - 1.5x
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	173	154
Year of Origination 2016 | 1.0x - 1.25x
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	162	166
Year of Origination 2016 | Less than 1.0x
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	71	76
Year of Origination 2016 | Commercial mortgage loans secured by land or construction loans
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	0	0
Year of Origination 2021
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	673	670
Year of Origination 2021 | Greater than 1.5x
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	562	556
Year of Origination 2021 | 1.25x - 1.5x
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	23	23
Year of Origination 2021 | 1.0x - 1.25x
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	33	34
Year of Origination 2021 | Less than 1.0x
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	55	57
Year of Origination 2021 | Commercial mortgage loans secured by land or construction loans
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	0	$ 0
Year of Origination 2022
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	73
Year of Origination 2022 | Greater than 1.5x
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	73
Year of Origination 2022 | 1.25x - 1.5x
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	0
Year of Origination 2022 | 1.0x - 1.25x
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	0
Year of Origination 2022 | Less than 1.0x
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	0
Year of Origination 2022 | Commercial mortgage loans secured by land or construction loans
Schedule of Loans by Debt Service Coverage Ratio [Line Items]
Commercial mortgage loans	$ 0