Supplemental Guarantor Information (Details 1) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008
CONDENSED CONSOLIDATING STATEMENT OF CASH FLOWS
CASH PROVIDED BY (USED IN) OPERATING ACTIVITIES	$ 9,953	$ 6,726	$ 4,224
CASH FLOWS FROM INVESTING ACTIVITIES:
Additions to oil and gas property	(6,414)	(4,407)	(3,326)
Additions to gas gathering, transmission and processing facilities	(664)	(515)	(306)
Acquisition of Mobil North Sea Limited	(1,246)
Acquisition of Devon properties		(1,018)
Acquisition of BP properties and facilities		(6,429)
Mariner Energy, Inc. merger		(787)
Acquisitions, other	(567)	(126)	(310)
Short-term investments			792
Restricted cash			14
Proceeds from sale of oil and gas properties	422		3
Other, net	(176)	(121)	(114)
NET CASH USED IN INVESTING ACTIVITIES	(8,645)	(13,403)	(3,247)
CASH FLOWS FROM FINANCING ACTIVITIES:
Commercial paper, credit facility and bank notes, net	(925)	(32)	248
Fixed-rate debt borrowings		2,470
Payments on fixed-rate notes		(1,023)	(100)
Proceeds from issuance of common stock		2,258
Proceeds from issuance of mandatory convertible preferred stock		1,227
Dividends paid	(306)	(226)	(209)	(7)
Common stock activity	52	70	28
Redemption of preferred stock			(98)
Other	32	19	21
NET CASH PROVIDED BY (USED IN) FINANCING ACTIVITIES	(1,147)	4,763	(110)
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	161	(1,914)	867
CASH AND CASH EQUIVALENTS AT BEGINNING OF YEAR	134	2,048	1,181
CASH AND CASH EQUIVALENTS AT END OF YEAR	295	134	2,048	1,181
Apache Corporation [Member]
CONDENSED CONSOLIDATING STATEMENT OF CASH FLOWS
CASH PROVIDED BY (USED IN) OPERATING ACTIVITIES	2,191	(1,848)	1,857
CASH FLOWS FROM INVESTING ACTIVITIES:
Additions to oil and gas property	(1,478)	(1,552)	(1,008)
Additions to gas gathering, transmission and processing facilities		(4)
Acquisition of Devon properties		(1,018)
Acquisitions, other	(448)		(196)
Short-term investments			792
Restricted cash			14
Proceeds from sale of oil and gas properties	204
Investment in and advances to subsidiaries, net	772	2,853	(657)
Other, net	(81)	(72)	(39)
NET CASH USED IN INVESTING ACTIVITIES	(1,031)	(5,499)	(1,094)
CASH FLOWS FROM FINANCING ACTIVITIES:
Commercial paper, credit facility and bank notes, net	(927)	928	1
Fixed-rate debt borrowings		2,470
Proceeds from issuance of common stock		2,258
Proceeds from issuance of mandatory convertible preferred stock		1,227
Dividends paid	(306)	(226)	(209)
Common stock activity	52	70	28
Redemption of preferred stock			(98)
Other	56	(21)	20
NET CASH PROVIDED BY (USED IN) FINANCING ACTIVITIES	(1,125)	6,706	(258)
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	35	(641)	505
CASH AND CASH EQUIVALENTS AT BEGINNING OF YEAR	6	647	142
CASH AND CASH EQUIVALENTS AT END OF YEAR	41	6	647
Apache Finance Canada [Member]
CONDENSED CONSOLIDATING STATEMENT OF CASH FLOWS
CASH PROVIDED BY (USED IN) OPERATING ACTIVITIES	13	(100)	(15)
CASH FLOWS FROM FINANCING ACTIVITIES:
Commercial paper, credit facility and bank notes, net			(3)
Intercompany borrowings	(1)	2
Common stock activity	(7)	96	18
NET CASH PROVIDED BY (USED IN) FINANCING ACTIVITIES	(8)	98	15
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	5	(2)
CASH AND CASH EQUIVALENTS AT BEGINNING OF YEAR	0	2	2
CASH AND CASH EQUIVALENTS AT END OF YEAR	5	0	2
All Other Subsidiaries of Apache Corporation [Member]
CONDENSED CONSOLIDATING STATEMENT OF CASH FLOWS
CASH PROVIDED BY (USED IN) OPERATING ACTIVITIES	7,749	8,674	2,382
CASH FLOWS FROM INVESTING ACTIVITIES:
Additions to oil and gas property	(4,936)	(2,855)	(2,318)
Additions to gas gathering, transmission and processing facilities	(664)	(511)	(306)
Acquisition of Mobil North Sea Limited	(1,246)
Acquisition of BP properties and facilities		6,429
Mariner Energy, Inc. merger		(787)
Acquisitions, other	(119)	(126)	(114)
Proceeds from sale of oil and gas properties	218		3
Other, net	(95)	(49)	(75)
NET CASH USED IN INVESTING ACTIVITIES	(6,842)	(10,757)	(2,810)
CASH FLOWS FROM FINANCING ACTIVITIES:
Commercial paper, credit facility and bank notes, net	2	(960)	903
Intercompany borrowings	(763)	2,720
Payments on fixed-rate notes		(1,023)	(100)
Common stock activity	(1)	35	(14)
Other	(24)	40	1
NET CASH PROVIDED BY (USED IN) FINANCING ACTIVITIES	(786)	812	790
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	121	(1,271)	362
CASH AND CASH EQUIVALENTS AT BEGINNING OF YEAR	128	1,399	1,037
CASH AND CASH EQUIVALENTS AT END OF YEAR	249	128	1,399
Reclassifications and Eliminations [Member]
CASH FLOWS FROM INVESTING ACTIVITIES:
Investment in and advances to subsidiaries, net	(772)	(2,853)	657
NET CASH USED IN INVESTING ACTIVITIES	(772)	2,853	657
CASH FLOWS FROM FINANCING ACTIVITIES:
Commercial paper, credit facility and bank notes, net			(653)
Intercompany borrowings	764	(2,722)
Common stock activity	8	(131)	(4)
NET CASH PROVIDED BY (USED IN) FINANCING ACTIVITIES	772	(2,853)	(657)
CASH AND CASH EQUIVALENTS AT BEGINNING OF YEAR	0	0	0
CASH AND CASH EQUIVALENTS AT END OF YEAR	$ 0	$ 0	$ 0