Investments - OTTI (Details) $ in Millions	3 Months Ended
	Mar. 31, 2022 USD ($) securities	Mar. 31, 2021 USD ($) securities
Available-for-sale Securities Including Securities Pledged [Line Items]
Impairment | $	$ 5	$ 0
No. of Securities | securities	11	7
Residential mortgage-backed
Available-for-sale Securities Including Securities Pledged [Line Items]
Impairment | $	$ 5	$ 0
No. of Securities | securities	11	6
Commercial mortgage-backed
Available-for-sale Securities Including Securities Pledged [Line Items]
Impairment | $	$ 0	$ 0
No. of Securities | securities	0	1