Amount of earned premiums ceded to other entities.

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-Name Accounting Standards Codification
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Name:	us-gaap_CededPremiumsEarned
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Reinsurance and indemnification - Premiums earned and life premiums and contract charges (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
National General Holdings Corp.
Reinsurance
Property and casualty insurance premiums earned			$ (631)
Property and casualty insurance premiums
Reinsurance
Property and casualty insurance premiums earned	$ (442)	$ (277)	(1,488)	$ (845)
Life premiums
Reinsurance
Accident and health insurance premiums and contract charges	$ (17)	$ (4)	$ (65)	$ (10)