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.

No definition available.

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- Definition

Amount, after effects of reinsurance, of expense (reversal of expense) for claims incurred and costs incurred in the claim settlement process.

+ References

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- Definition

Amount, after effects of reinsurance, of payments to settle insured claims and pay costs incurred in the claims settlement process.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 40
-Section 50
-Paragraph 3
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3536-108585

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Reserve for Property and Casualty Insurance Claims and Claims Expense - Reconciliation of total claims and claims expense incurred and paid by coverage (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Increase (decrease) in claims and claims expense
Incurred	$ 29,318	$ 22,001	$ 23,976
Property and casualty
Increase (decrease) in claims and claims expense
Incurred	29,318
Paid	(28,245)	(22,224)	(23,444)
Claims incurred and paid from before 2017 \| Property and casualty
Increase (decrease) in claims and claims expense
Incurred	(69)
Paid	(622)
Auto insurance - liability coverage \| Property and casualty
Increase (decrease) in claims and claims expense
Incurred	10,830
Paid	(9,420)
Auto insurance - physical damage coverage \| Property and casualty
Increase (decrease) in claims and claims expense
Incurred	7,170
Paid	(7,150)
Homeowners \| Property and casualty
Increase (decrease) in claims and claims expense
Incurred	6,371
Paid	(6,045)
Total auto and homeowners insurance \| Property and casualty
Increase (decrease) in claims and claims expense
Incurred	24,371
Paid	(22,615)
Other personal lines \| Property and casualty
Increase (decrease) in claims and claims expense
Incurred	1,144
Paid	(1,163)
Commercial lines \| Property and casualty
Increase (decrease) in claims and claims expense
Incurred	767
Paid	(581)
Protection Services \| Property and casualty
Increase (decrease) in claims and claims expense
Incurred	376
Paid	(373)
Run-off Property-Liability \| Property and casualty
Increase (decrease) in claims and claims expense
Incurred	109
Paid	(97)
Unallocated loss adjustment expenses (“ULAE”) \| Property and casualty
Increase (decrease) in claims and claims expense
Incurred	2,569
Paid	(2,726)
Other (1) \| Property and casualty
Increase (decrease) in claims and claims expense
Incurred	51
Paid	(68)
Catastrophe losses
Increase (decrease) in claims and claims expense
Incurred	$ 3,340	$ 2,810	$ 2,560