Summary of Significant Accounting Policies - Allowance For Credit Loss (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Fixed income securities			$ 0
Investments	$ 73	$ 136
Premium installment receivables	107	153	91
Reinsurance recoverables	74	60
Other assets	26	17
Assets	280	366
Commitments to fund mortgage loans and bank loans	0	1
Liabilities	0	1
Total	280	367
Fixed income securities
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Fixed income securities	6	2
Mortgage loans
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance credit losses	6	67	$ 3
Bank loans
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance credit losses	$ 61	$ 67