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Amount of increase in allowance for credit loss on reinsurance recoverable, from recovery.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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Amount of expense (reversal of expense) for expected credit loss on reinsurance recoverable.

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Amount of allowance for credit loss on reinsurance recoverable.

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Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

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Reinsurance - Reinsurance Recoverable, ACL (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Jan. 01, 2020	Dec. 31, 2019
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Reinsurance Recoverable, Credit Loss Expense (Reversal)	$ (9)	$ 4
Reinsurance, Loss on Uncollectible Accounts in Period, Amount	1	0
Reinsurance Recoverable, Allowance for Credit Loss, Recovery	0	1
Reinsurance Recoverable, Allowance for Credit Loss	45	55		$ 48
Corporate
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Reinsurance Recoverable, Credit Loss Expense (Reversal)	0	1
Reinsurance, Loss on Uncollectible Accounts in Period, Amount	0	0
Reinsurance Recoverable, Allowance for Credit Loss, Recovery	0	0
Reinsurance Recoverable, Allowance for Credit Loss	2	2		0
Operating Segments \| Property and Casualty Insurance Subsidiaries
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Reinsurance Recoverable, Credit Loss Expense (Reversal)	(9)	3
Reinsurance, Loss on Uncollectible Accounts in Period, Amount	1	0
Reinsurance Recoverable, Allowance for Credit Loss, Recovery	0	1
Reinsurance Recoverable, Allowance for Credit Loss	42	52		48
Operating Segments \| Group Insurance Policy [Member]
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Reinsurance Recoverable, Credit Loss Expense (Reversal)	0	0
Reinsurance, Loss on Uncollectible Accounts in Period, Amount	0	0
Reinsurance Recoverable, Allowance for Credit Loss, Recovery	0	0
Reinsurance Recoverable, Allowance for Credit Loss	1	1		0
Uncollectible reinsurance
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Reinsurance Recoverable, Allowance for Credit Loss	99	108		114
Uncollectible reinsurance \| Corporate
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Reinsurance Recoverable, Allowance for Credit Loss	2	2		0
Uncollectible reinsurance \| Operating Segments \| Property and Casualty Insurance Subsidiaries
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Reinsurance Recoverable, Allowance for Credit Loss	96	105		114
Uncollectible reinsurance \| Operating Segments \| Group Insurance Policy [Member]
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Reinsurance Recoverable, Allowance for Credit Loss	1	1		0
Disputes [Member]
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Reinsurance Recoverable, Allowance for Credit Loss	54	53		66
Disputes [Member] \| Corporate
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Reinsurance Recoverable, Allowance for Credit Loss	0	0		0
Disputes [Member] \| Operating Segments \| Property and Casualty Insurance Subsidiaries
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Reinsurance Recoverable, Allowance for Credit Loss	54	53		66
Disputes [Member] \| Operating Segments \| Group Insurance Policy [Member]
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Reinsurance Recoverable, Allowance for Credit Loss	$ 0	$ 0		0
Cumulative Effect, Period of Adoption, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member]
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest				2
Cumulative Effect, Period of Adoption, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member] \| Corporate
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest				1
Cumulative Effect, Period of Adoption, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member] \| Operating Segments \| Property and Casualty Insurance Subsidiaries
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest				0
Cumulative Effect, Period of Adoption, Adjustment [Member] \| Accounting Standards Update 2016-13 [Member] \| Operating Segments \| Group Insurance Policy [Member]
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest				1
Cumulative Effect, Period of Adoption, Adjusted Balance [Member]
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Reinsurance Recoverable, Allowance for Credit Loss				50
Cumulative Effect, Period of Adoption, Adjusted Balance [Member] \| Corporate
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Reinsurance Recoverable, Allowance for Credit Loss				1
Cumulative Effect, Period of Adoption, Adjusted Balance [Member] \| Operating Segments \| Property and Casualty Insurance Subsidiaries
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Reinsurance Recoverable, Allowance for Credit Loss				48
Cumulative Effect, Period of Adoption, Adjusted Balance [Member] \| Operating Segments \| Group Insurance Policy [Member]
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Reinsurance Recoverable, Allowance for Credit Loss				$ 1
Cumulative Effect, Period of Adoption, Adjusted Balance [Member] \| Uncollectible reinsurance
Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward]
Reinsurance Recoverable, Allowance for Credit Loss			$ 116