Receivables (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Receivables [Abstract]
Reinsurance (Note 16)	$ 4,478	$ 4,204
Insurance	2,640	2,481
Receivable from brokers	97	124
Accrued investment income	381	395
Federal income taxes	4	14
Other, primarily customer accounts	290	520
Total	7,890	7,738
Less: allowance for doubtful accounts on reinsurance receivables	21	25
Less: allowance for other doubtful accounts	36	38
Receivables	$ 7,833	$ 7,675

Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business.

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Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business.

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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 allowance for credit loss on accounts receivable.

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Carrying amount as of the balance sheet date of income taxes previously overpaid to tax authorities (such as U.S. Federal, state and local tax authorities) representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes. Also called income tax refund receivable.

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Amount due from parties in nontrade transactions, classified as other.

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Gross amount, as of the balance sheet date, due the entity from (a) agents and insureds, (b) uncollected premiums and (c) others, before deducting the allowance for doubtful accounts.

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Amount receivable from broker-dealers and clearing organizations, including, but not limited to, securities failed-to-deliver, certain deposits for securities borrowed, open transactions, good faith and margin deposits, commissions and floor brokerage receivables.

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Amount of allowance for credit loss on reinsurance recoverable.

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Amount before valuation allowance recoverable under reinsurance contracts. Examples include, but are not limited to, settled and unsettled claims, incurred but not reported losses, loss adjustment expense, premium paid, policy benefits and policy reserves.

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