Segment Information (Balance Sheet) (Details) (USD $)	Jun. 30, 2011		Dec. 31, 2010	Jun. 30, 2010
Current assets	$ 8,911,000,000	[1]	$ 5,555,000,000
Property and equipment, net	22,427,000,000		19,652,000,000
Goodwill	6,176,000,000		6,080,000,000
Other assets	1,023,000,000
Total assets	38,537,000,000		32,927,000,000
Current liabilities	4,484,000,000		4,583,000,000
Long-term debt	5,968,000,000		3,819,000,000
Asset retirement obligations	1,499,000,000		1,423,000,000	1,346,000,000
Other liabilities	810,000,000
Deferred income taxes	4,348,000,000		2,756,000,000
Stockholders' equity	21,428,000,000		19,253,000,000
Total liabilities and stockholders' equity	38,537,000,000		32,927,000,000
Cash, cash equivalents and short-term investments	6,700,000,000
U.S. [Member]
Current assets	1,916,000,000	[1]
Property and equipment, net	14,472,000,000
Goodwill	3,046,000,000
Other assets	538,000,000
Total assets	19,972,000,000
Current liabilities	1,995,000,000
Long-term debt	4,725,000,000
Asset retirement obligations	578,000,000
Other liabilities	742,000,000
Deferred income taxes	2,939,000,000
Stockholders' equity	8,993,000,000
Total liabilities and stockholders' equity	19,972,000,000
Canada [Member]
Current assets	6,959,000,000	[1]
Property and equipment, net	7,955,000,000
Goodwill	3,130,000,000
Other assets	391,000,000
Total assets	18,435,000,000
Current liabilities	2,446,000,000
Long-term debt	1,243,000,000
Asset retirement obligations	921,000,000
Other liabilities	66,000,000
Deferred income taxes	1,409,000,000
Stockholders' equity	12,350,000,000
Total liabilities and stockholders' equity	18,435,000,000
Cash, cash equivalents and short-term investments	6,100,000,000
International [Member]
Current assets	36,000,000	[1]
Other assets	94,000,000
Total assets	130,000,000
Current liabilities	43,000,000
Other liabilities	2,000,000
Stockholders' equity	85,000,000
Total liabilities and stockholders' equity	$ 130,000,000

[1] Current assets in the Canadian segment include $6.1 billion of cash, cash equivalents and short-term investments that were generated from Devon's International offshore divestiture program and have not been repatriated to the United States.