The number of purported class action suits filed against TPC and other insurers in state court in West Virginia relative to asbestos direct action litigation.

No definition available.

+ Details

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Namespace Prefix:	trv_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of gain (loss) recognized in settlement of litigation and insurance claims. Excludes claims within an insurance entity's normal claims settlement process.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

+ Details

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Period Type:	duration

- Definition

Amount of judgment or settlement awarded to (against) the entity in respect of litigation.

+ References

No definition available.

+ Details

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- Definition

Interest expense (income) directly attributable to an award in settlement of litigation.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Details

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- Details

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- Details

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Contingencies, Commitments and Guarantees (details) - Loss Contingencies (USD $) In Millions, unless otherwise specified	7 Months Ended	12 Months Ended	1 Months Ended
	Apr. 30, 2002 item	Dec. 31, 2014	Nov. 30, 2003	May 31, 2004
Asbestos Direct Action Litigation [Member]
Loss Contingencies
Number of purported class action suits filed against TPC and other insurers in state court in West Virginia relative to asbestos direct action litigation	2
Settlement amount		$ 502
Total settlement amount		579
Interest related to settlement award		77
Statutory and Hawaii Actions [Member] \| Maxiumum [Member]
Loss Contingencies
Settlement amount			412
Common Law Claims [Member] \| Maxiumum [Member]
Loss Contingencies
Settlement amount				$ 90