v3.25.3

Share-Based Incentive Compensation (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Share-Based Payment Arrangement [Abstract]
Stock options vested at end of period, number (in shares)	5,804,107		5,804,107
Stock options vested at end of period, weighted average exercise price (in dollars per share)	$ 159.98		$ 159.98
Stock options vested at end of period, weighted average contractual life remaining (in years)			5 years 4 months 24 days
Stock options vested at end of period, aggregate intrinsic value	$ 692		$ 692
Stock options exercisable at end of period, number (in shares)	4,388,364		4,388,364
Stock options exercisable at end of period, weighted average exercise price (in dollars per share)	$ 142.96		$ 142.96
Stock options exercisable at end of period, weighted average contractual life remaining (in years)			4 years 6 months
Stock options exercisable at end of period, aggregate intrinsic value	$ 598		$ 598
Total compensation cost recognized in earnings for all share-based incentive compensation awards	59	$ 63	199	$ 202
Tax benefit recognized in the consolidated statement of income related to compensation costs	11	$ 11	33	$ 33
Total unrecognized compensation cost related to all nonvested share-based incentive compensation awards	$ 310		$ 310
Weighted-average period of recognition for unrecognized compensation cost (in years)			1 year 10 months 24 days

Amount of difference between fair value of the underlying shares reserved for issuance and exercise prices of fully vested options outstanding.

+ References

No definition available.

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- Definition

As of the balance sheet date, the number of shares into which fully vested stock options outstanding can be converted under the option plan.

+ References

No definition available.

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- Definition

As of the balance sheet date, the weighted-average exercise price for outstanding stock options that are fully vested.

+ References

No definition available.

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- Definition

Weighted average remaining contractual term for fully vested options outstanding.

+ References

No definition available.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section S45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479983/718-10-S45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479830/718-10-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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- References

No definition available.

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iii)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

+ References

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- Definition

Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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- Definition

Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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TRAVELERS COMPANIES, INC. 10-Q