Annual estimate of forfetures for equity awards

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- Definition

The maximum amount of an employee's compensation that can be contributed for stock purchases under the employee stock purchase plan in any calendar year.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Number of share available for issuance under employee stock purchase 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

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.

+ References

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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.

+ 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 (j)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3255-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

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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

+ Details

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- Definition

The number of grants made 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

+ Details

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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

+ Details

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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

+ 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

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

+ References

No definition available.

+ Details

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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).

+ References

+ Details

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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

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

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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.

+ References

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 29, 30
-Article 5

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- Definition

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

+ References

+ Details

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- Details

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- Details

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Share-based compensation (Narrative) (Detail) - USD ($)	12 Months Ended
Share-based compensation (Narrative) (Detail) - USD ($)	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2004
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense related to the unvested share-based awards	$ 175,000,000
Weighted-average expected recognition period for the unrecognized compensation expense	1 year
Weighted average remaining contractual term for stock options outstanding	6 years
Weighted-average remaining contractual term for stock options exercisable	4 years 8 months 20 days
Cash received from exercise of stock options	$ 86,000,000
Restricted stock awards granted to non-management directors	24,945.00	25,339	20,969
Amounts paid during period by employees for the purchase of shares under the ESPP	$ 18,000,000	$ 17,000,000	$ 14,000,000
Number of shares purchased during period by employees pursuant to the provisions of the ESPP	197,442	181,901	175,437
Discounted purchase price from market price	85.00%
Annual estimate of forfeitures for equity awards	6.50%	6.50%	6.50%
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]
Restricted stock units awarded to employees and officers of ACE and subsidiaries during period	1,124,143	1,295,734	1,347,679
Weighted average grant-day fair value of restricted stock units granted to employees and officers of the company (US$ per share)	$ 114.28	$ 97.04	$ 85.61
Number of unvested restricted stock units outstanding	2,825,757	3,193,518	3,511,690	4,015,732
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units awarded to employees and officers of ACE and subsidiaries during period	293,822	300,511	271,004
Weighted average grant-day fair value of restricted stock units granted to employees and officers of the company (US$ per share)	$ 114.71	$ 97.66	$ 85.44
Number of unvested restricted stock units outstanding	663,412
Number of deferred restricted stock units	145,751
ACE Limited 2004 Long-Term Incentive Plan \| Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of award	4 years
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee Stock Purchase Plan Authorized Amount	$ 25,000
Discounted purchase price from market price	85.00%
Common shares \| ACE Limited 2004 Long-Term Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares authorized for issuance under plan					38,600,000
Common shares remaining as available for issuance under the ESPP	4,617,796
Increase to authorized shares approved by shareholders	8,000,000
Common shares \| ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares authorized for issuance under plan					4,500,000
Common shares remaining as available for issuance under the ESPP	934,243