Investments - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Dec. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Net investment income
Mortgage loans, net	$ 3,359	$ 2,951	$ 3,359
Threshold percentage of mortgage loans to total carrying value		5.00%
Fair value	23,907	$ 17,937	23,907
Threshold percentage of municipal to total carrying value		5.00%
Short-term investments	974	$ 1,035	974
Policy loans	582	525	582
Fixed income and equity securities loaned	322		322
Interest income on collateral, net of fees			1	$ 1
Below investment grade assets	2,990	1,340	2,990
Fixed income securities and short-term investments deposited with regulatory authorities		24
Non-income producing fixed income securities and other investments		2
Accrued investment income	231	155	231
Net gains and losses on investments and derivatives	4	624	266	341
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	817	2,007
Fixed income securities
Net investment income
Accrued investment income	198	131	198
Mortgage loans
Net investment income
Accrued investment income	13	11	13
Reduction of allowance related to sales		4	15
Allowance for credit loss	59	$ 27	59	$ 3
Agent loans
Net investment income
Accrued investment income	2		2
Agent loans, high credit quality (in percentage)		85.00%
Allowance for credit loss	5	$ 0	5
Bank loans
Net investment income
Accrued investment income	1		1
Allowance for credit loss	$ 16	$ 7	$ 16

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

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