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The reserve to cover probable credit losses related to specifically identified fixed maturity real estate loans as well as probable credit losses inherent in the remainder of that loan portfolio.

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Carrying amount of cash and investment securities on deposit with state regulatory authorities in connection with capital requirements.

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The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

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Investments - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
Investments - Narrative (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Investment [Line Items]
Fixed income securities	$ 66,354	$ 59,044
Short-term investments	7,800	4,260
Fixed income and equity securities carrying value	1,190	1,740
Interest income on collateral, net of fees	3	5	$ 4
Debt Securities below Investment Grade	9,000	7,150
Fixed income and short-term investments carrying value	141
Non-income producing fixed income securities	80
Accrued investment income	600	600
Mortgage loans, net	$ 4,075	4,817
Percentage of credit concentration risk of single issuer and affiliates of shareholder's equity	10.00%
Fixed income securities
Investment [Line Items]
Accrued investment income	$ 548
Mortgage loans on real estate
Investment [Line Items]
Accrued investment income	15
Agent loans
Investment [Line Items]
Accrued investment income	$ 2
High credit quality, percentage	85.00%
Allowance	$ (5)
Bank loans
Investment [Line Items]
Accrued investment income	4
Municipal
Investment [Line Items]
Fixed income securities	9,587	8,620
Mortgage loans on real estate
Investment [Line Items]
Mortgage loans, net	4,075	4,817
Allowance	$ (67)	$ (3)