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 expense (reversal of expense) for claims incurred in prior reporting periods and related claims settlement costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 40
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=65670824&loc=d3e14764-158437

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 235
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-18)
-URI http://asc.fasb.org/extlink&oid=34713774&loc=d3e575016-122915

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Reserve for Property-Liability Insurance Claims and Claims Expense (Details 2) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Increase (decrease) in claims and claims expense
Prior years claims and claims adjust expense, favorable	$ 321
Auto
Increase (decrease) in claims and claims expense
Prior years claims and claims adjust expense, favorable	336
Catastrophe
Increase (decrease) in claims and claims expense
Total incurred	2,640	$ 2,270
Non Catastrophe Reestimates \| Homeowners
Increase (decrease) in claims and claims expense
Prior years claims and claims adjust expense, favorable	86
Reserve Adjustments \| Discontinued Lines and Coverages Product Line
Increase (decrease) in claims and claims expense
Prior years claims and claims adjust expense, favorable	93
Reserve Adjustments \| Other personal lines
Increase (decrease) in claims and claims expense
Prior years claims and claims adjust expense, favorable	(8)
Catastrophe Loss Re-estimates
Increase (decrease) in claims and claims expense
Prior years claims and claims adjust expense, favorable	$ 10