Acquisitions and divestitures.

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- Definition

Business Acquisition Percentage Of Voting Interests Acquired Retained.

+ Details

Name:	apa_BusinessAcquisitionPercentageOfVotingInterestsAcquiredRetained
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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Period of pipeline agreement.

+ Details

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Period Type:	duration

- Definition

Period of provision of renewals.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Preferential purchase right.

+ Details

Name:	apa_PreferentialPurchaseRight
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 51
-Subparagraph d
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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- Definition

Percentage of voting equity interests acquired in the business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141R
-Paragraph 68
-Subparagraph 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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6909870&loc=d3e1392-128463

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- Definition

The amount of acquisition cost of a business combination allocated to liabilities assumed.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141
-Paragraph 37
-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 Emerging Issues Task Force (EITF)
-Number 98-1
-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.

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Balance Type:	credit
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- Definition

This element represents the acquisition-date fair value of the total consideration transferred which consists of the sum of the acquisition-date fair values of the assets transferred by the acquirer, the liabilities incurred by the acquirer to former owners of the acquiree, and the equity interests issued by the acquirer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6911361&loc=d3e6927-128479

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141R
-Paragraph 39, 40
-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 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141R
-Paragraph 68
-Subparagraph f
-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 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6613-128477

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Acquisitions and Divestitures (Details Textuals) (USD $)														3 Months Ended
	Mar. 31, 2011	Aug. 10, 2010	Jul. 31, 2010	Nov. 30, 2010 Mariner Energy Inc [Member]	Jun. 30, 2010 Gulf of Mexico, Devon [Member]	Dec. 31, 2010 Kitimat LNG [Member] Apache Canada [Member]	Dec. 31, 2010 Kitimat LNG [Member] EOG Canada [Member]	Mar. 31, 2011 Kitimat LNG [Member] Encana [Member]	Feb. 28, 2011 Pacific Trails Pipeline [Member] Apache Canada [Member]	Dec. 31, 2010 Pacific Trails Pipeline [Member] Apache Canada [Member]	Feb. 28, 2011 Pacific Trails Pipeline [Member] EOG Canada [Member]	Dec. 31, 2010 Pacific Trails Pipeline [Member] EOG Canada [Member]	Aug. 10, 2010 BP's Oil And Gas Operations [Member]	Jun. 30, 2011 PNG [Member]	Mar. 31, 2011 PTP and Kitimat LNG [Member] Apache Canada [Member]	Mar. 31, 2011 PTP and Kitimat LNG [Member] EOG Canada [Member]	Jul. 31, 2010 Bp Acquisitions [Member]	Oct. 08, 2010 Western Canada Sedimentary Basin [Member]	Nov. 04, 2010 Western Desert, Egypt [Member]
Acquisitions and Divestitures (Textuals) [Abstract]
Percentage of acquisition						51.00%	49.00%	30.00%	51.00%	25.50%	49.00%	24.50%			40.00%	30.00%
Total consideration transferred				$ 2,700,000,000											$ 50,000,000
Percentage of retained interest in acquisition	40.00%
Period of provision of renewals														5 years
Period of pipeline agreement														7 years
Purchase price of acquisition			6,400,000,000		1,050,000,000								3,100,000,000				7,000,000,000	3,250,000,000	650,000,000
Preferential purchase right		658,000,000
Liabilities assumed				$ 1,700,000,000