Investments (excluding Consolidated Investment Entities) - OTTI (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021 USD ($) security	Sep. 30, 2020 USD ($) security	Sep. 30, 2021 USD ($) security	Sep. 30, 2020 USD ($) security
Available-for-sale Securities, Including Securities Pledged [Line Items]
Impairment | $	$ 0	$ 10	$ 0	$ 80
No. of Securities | security	2	84	11	412
State, municipalities and political subdivisions
Available-for-sale Securities, Including Securities Pledged [Line Items]
Impairment | $	$ 0	$ 0	$ 0	$ 0
No. of Securities | security	0	2	0	13
U.S. corporate public securities
Available-for-sale Securities, Including Securities Pledged [Line Items]
Impairment | $	$ 0	$ 2	$ 0	$ 32
No. of Securities | security	0	18	0	80
U.S. corporate private securities
Available-for-sale Securities, Including Securities Pledged [Line Items]
Impairment | $	$ 0	$ 1	$ 0	$ 1
No. of Securities | security	0	4	0	9
Foreign corporate public securities and foreign governments
Available-for-sale Securities, Including Securities Pledged [Line Items]
Impairment | $	$ 0	$ 0	$ 0	$ 4
No. of Securities | security	0	12	0	39
Foreign corporate private securities
Available-for-sale Securities, Including Securities Pledged [Line Items]
Impairment | $	$ 0	$ 2	$ 0	$ 8
No. of Securities | security	0	5	0	17
Residential mortgage-backed
Available-for-sale Securities, Including Securities Pledged [Line Items]
Impairment | $	$ 0	$ 1	$ 0	$ 6
No. of Securities | security	2	24	10	56
Commercial mortgage-backed securities
Available-for-sale Securities, Including Securities Pledged [Line Items]
Impairment | $	$ 0	$ 4	$ 0	$ 28
No. of Securities | security	0	18	1	124
Other asset-backed securities
Available-for-sale Securities, Including Securities Pledged [Line Items]
Impairment | $	$ 0	$ 0	$ 0	$ 1
No. of Securities | security	0	1	0	74