The number of shares available to be earned in a future period related to grants made in previous years.

No definition available.

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Namespace Prefix:	apc_
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- Definition

The number of shares earned during the period related to grants made in previous years.

+ References

No definition available.

+ Details

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- Definition

Date the equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

The number of shares deferred during the reporting period under the plan.

+ References

No definition available.

+ Details

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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

+ Details

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- Definition

Aggregate unrecognized cost of share-based awards, other than options, made to employees under an equity-based compensation plan, that have yet to vest.

+ References

No definition available.

+ Details

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- Definition

Aggregate unrecognized cost of option awards made to employees under a stock option plan or plans, that have yet to vest.

+ 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

+ 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

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph c(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(2)(c)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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- Definition

The total fair value of equity-based awards for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

+ References

+ 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

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph a

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(3)

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

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- Definition

The total accumulated difference between fair values of underlying shares on dates of exercise and exercise price on options which were exercised (or share units converted) into shares during the reporting period under the plan.

+ References

+ Details

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Period Type:	duration

- 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 Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph c(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: 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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- 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

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph 65

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Share-Based Compensation - Equity-Classified Awards (Detail) (USD $)	12 Months Ended			60 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2012
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Shares of common stock authorized	31,000,000			31,000,000
Restricted Stock [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Weighted-average grant-date fair value	$ 79.97	$ 81.19	$ 68.51
Total fair value	$ 105,000,000	$ 124,000,000	$ 122,000,000
Total unrecognized compensation cost	148,000,000			148,000,000
Unrecognized compensation cost, weighted-average remaining period	1 year 10 months 24 days
Restricted Stock [Member] \| Maximum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting period	3 years
Stock Option [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting period	3 years
Unrecognized compensation cost, weighted-average remaining period	2 years
Weighted-average grant-date fair value	$ 25.84	$ 29.77	$ 26.44
Total intrinsic value of stock options exercised during the period	49,000,000	45,000,000	62,000,000
Total unrecognized compensation cost related to stock options	46,000,000			46,000,000
Stock Option [Member] \| Maximum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Expiration date	7 years
Stock Option [Member] \| Director [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting period	1 year
Stock Option [Member] \| Director [Member] \| Maximum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Expiration date	10 years
Performance-Based Share Awards [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Total fair value		6,000,000	17,000,000
Total unrecognized compensation cost	$ 0			$ 0
Shares earned				521,258
Shares available to be earned in the future	0
Shares issued	0			386,574
Shares deferred pursuant to the agreements				134,684
Performance-Based Share Awards [Member] \| Minimum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting period	1 year
Performance-Based Share Awards [Member] \| Maximum [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Vesting period	3 years
Shares of common stock authorized	934,424			934,424