Annual estimate of forfetures for equity awards

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- Definition

Restricted Stock Units Issued To Non-management Directors During Period, Shares, Restricted Stock Award

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- Definition

The number of deferred restricted stock units outstanding at the end of the period.

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- Definition

Number of share available for issuance under employee stock purchase plans.

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- Definition

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

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- Definition

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

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No definition available.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

This item represents the amount of cash contributions during the period made by the entity to the Employee Stock Ownership Plan (ESOP).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 40
-Section 50
-Paragraph 1
-Subparagraph (a)
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- Definition

Sum of the allocated, committed-to-be-released and suspense shares of the entity held by the plan.

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- Definition

The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

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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

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

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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.

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No definition available.

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- Definition

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

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- Definition

Number of additional shares authorized for issuance under an established share-based compensation plan.

+ References

No definition available.

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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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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- Definition

Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Purchase price of common stock expressed as a percentage of its fair value.

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No definition available.

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- Definition

Value, after forfeitures, of stock or other type of equity granted of any equity-based compensation plan other than an employee stock ownership plan (ESOP).

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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

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- Definition

Aggregate change in value for stock issued during the period as a result of employee stock purchase plan.

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Share-based compensation (Narrative) (Detail) - USD ($)		12 Months Ended
Share-based compensation (Narrative) (Detail) - USD ($)	Jan. 14, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense related to the unvested share-based awards		$ 260,000,000
Weighted-average expected recognition period for the unrecognized compensation expense		1 year
Weighted average remaining contractual term for stock options outstanding		6 years 1 month
Weighted-average remaining contractual term for stock options exercisable		4 years 8 months 20 days
Cash received from exercise of stock options		$ 112,000,000
Restricted stock awards granted to non-management directors		23,812	24,945	25,339
Amounts paid during period by employees for the purchase of shares under the ESPP		$ 24,000,000	$ 18,000,000	$ 17,000,000
Number of shares purchased during period by employees pursuant to the provisions of the ESPP		211,492	197,442	181,901
Discounted purchase price from market price for the ESPP		85.00%
Annual estimate of forfeitures for equity awards		6.50%	6.50%	6.50%
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Rate for the ESPP		10.00%
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee Stock Purchase Plan Authorized Amount		$ 25,000
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of award		3 years
Stock option term in years		10 years
Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of unvested restricted stock outstanding		5,805,126	3,489,169	3,837,097	4,129,583
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of deferred restricted stock units		519,331
ACE Limited 2004 Long-Term Incentive Plan [Member] \| Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of award		4 years
Common shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares remaining as available for issuance under the 2016 LTIP		722,751
Employee Stock Ownership Plan (ESOP), Shares in ESOP		4,500,000
Common shares \| ACE Limited 2004 Long-Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase to authorized shares approved by shareholders		8,000,000
Common shares \| Chubb Limited 2016 Long-Term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares authorized for issuance under plan		19,500,000
Common shares remaining as available for issuance under the 2016 LTIP		20,522,230.00
The Chubb Corporation [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Value of Equity Awards Issued in Acquisition	$ 525,000,000
Attributed Value Equity Awards Assumed in Acquisition	$ 323,000,000