Investments - Credit Quality of RMLs (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Financing Receivable, Credit Quality Indicator [Line Items]
Loans, net	$ 1,614	$ 0
Performing
Financing Receivable, Credit Quality Indicator [Line Items]
Carrying Value	$ 997
% of Total	91.00%
Non-performing
Financing Receivable, Credit Quality Indicator [Line Items]
Carrying Value	$ 99
% of Total	9.00%
Residential Portfolio Segment | Over 90 days past due
Financing Receivable, Credit Quality Indicator [Line Items]
Carrying Value	$ 1,096
Allowance for expected loan loss	33
Loans, net	$ 1,063
% of Total	100.00%
Allowance % of Total	0.00%