Investments - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Dec. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Net investment income
Mortgage loans, net	$ 3,359	$ 3,359	$ 3,988
Threshold percentage of mortgage loans to total carrying value	5.00%	5.00%
Fair value	$ 23,907	$ 23,907	21,725
Threshold percentage of municipal to total carrying value	5.00%	5.00%
Short-term investments	$ 974	$ 974	1,191
Policy loans	582	582	557
Fixed income and equity securities loaned	322	322	506
Interest income on collateral, net of fees		1	1	$ 1
Below investment grade assets	2,990	2,990	2,830
Fixed income securities and short-term investments deposited with regulatory authorities	21	21
Non-income producing fixed income securities and other investments	38	38
Accrued investment income	231	231	239
Realized capital gains and losses	4	266	341	(175)
Mortgage loans
Net investment income
Payments to acquire investments	217
Reduction of allowance related to sales	15
Municipal
Net investment income
Fair value	2,007	2,007	1,755
Fixed income securities
Net investment income
Accrued investment income	198	198
Realized capital gains and losses		54	25	(40)
Mortgage loans
Net investment income
Accrued investment income	13	13
Reduction of allowance related to sales		15
Realized capital gains and losses		(45)	$ 0	$ 2
Agent loans
Net investment income
Accrued investment income	$ 2	$ 2
Agent loans, high credit quality (in percentage)	85.00%	85.00%
Allowance for agent loans	$ (5)	$ (5)
Bank loans
Net investment income
Accrued investment income	$ 1	$ 1

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Below investment grade assets included in fixed income securities.

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Finance Receivables, Allowance for Credit Loss, Securities Sold

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The minimum percentage of mortgage loans to total carrying value that is used as a threshold for disclosure.

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The minimum percentage of municipal bonds to total carrying value that is used as a threshold for disclosure.

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Interest earned on collateral received for loaned securities and invested in short-term investments and fixed income securities, net of fees.

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Interest, dividends, rents, ancillary and other revenues earned but not yet received by the entity on its investments.

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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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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount before allowance of loans made to policy and contract holders using their life insurance contracts' cash value or separate accounts as collateral. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums over and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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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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Amount of short-term investments classified as other.

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The cash outflow associated with the purchase of all investments (debt, security, other) during the period.

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The net realized gains or losses on investments during the period, not including gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of securities loaned to entities in exchange for collateral, not subject to a master netting arrangement.

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