Attributed Value Equity Awards Assumed in Acquisition

No definition available.

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- Definition

The number of shares issuable under a share-based award plan pertaining to grants made to officers of the Company and its subsidiaries during the period on other than stock option plans.

+ References

No definition available.

+ Details

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- Definition

Description of the period of time an employee has to exercise their options.

+ References

No definition available.

+ Details

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- Definition

Description of the period of time over which an employee's right to exercise their stock and stock units is no longer contingent on satisfaction of either a service period, service condition, market condition or a performance condition, which may be expressed in a variety of ways (for example, in years, month and year).

+ References

No definition available.

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- Definition

Total Value of Equity Awards Issued in Acquisition, including the portion attributable to post-acquisition services.

+ References

No definition available.

+ Details

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

Net number of share options (or share units) granted during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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Balance Type:	na
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- Definition

Number of share instruments newly issued under a share-based compensation plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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- Details

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- Details

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- Details

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Share-Based Compensation (Detail) - USD ($) $ / shares in Units, $ in Millions			3 Months Ended
	Feb. 25, 2016	Jan. 14, 2016	Mar. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option vesting period in years			3 years
Stock option term in years			10 years
The Chubb Corporation [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option term in years			10 years
Restricted stock award and units vesting period in years			3 years
Attributed Value Equity Awards Assumed in Acquisition		$ 323
Total Value of Equity Awards Issued in Acquisition		$ 525
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted	1,926,842
Weighted-average grant date fair value for stock options granted	$ 21.52
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock award and units vesting period in years			4 years
Restricted stock awards granted to employees and officers of the company	1,119,686
Grant date fair value of awards except for options granted to employees and officers of the company	$ 118.39
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units awarded to employees and officers of the company	337,581
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock award and units vesting period in years			4 years
Restricted stock units awarded to employees and officers of the company	452,820