Suspended Exploratory Well Costs	3 Months Ended
Mar. 31, 2013
Disclosure Text Block [Abstract]
Suspended Exploratory Well Costs	5. Suspended Exploratory Well Costs The Company's suspended exploratory well costs were $1.9 billion at March 31, 2013, and $2.1 billion at December 31, 2012. The decrease in suspended exploratory well costs during 2013 primarily resulted from costs charged to dry hole expense in Sierra Leone, reclassification of costs to proved properties in the Marcellus and Utica shales in the Southern and Appalachia Region, and the sale of the Company's interest in Indonesian subsidiaries, partially offset by the capitalization of costs associated with exploration drilling in Brazil. During the three months ended March 31, 2013, $95 million of exploratory well costs previously capitalized as suspended exploratory well costs for greater than one year at December 31, 2012, were charged to dry hole expense. Management believes projects with suspended exploratory well costs exhibit sufficient quantities of hydrocarbons to justify potential development and is actively pursuing efforts to assess whether reserves can be attributed to these projects. If additional information becomes available that raises substantial doubt as to the economic or operational viability of any of these projects, the associated costs will be expensed at that time.

Suspended Exploratory Well Costs

3 Months Ended

Mar. 31, 2013

5. Suspended Exploratory Well Costs

The Company's suspended exploratory well costs were $1.9 billion at March 31, 2013, and $2.1 billion at December 31, 2012. The decrease in suspended exploratory well costs during 2013 primarily resulted from costs charged to dry hole expense in Sierra Leone, reclassification of costs to proved properties in the Marcellus and Utica shales in the Southern and Appalachia Region, and the sale of the Company's interest in Indonesian subsidiaries, partially offset by the capitalization of costs associated with exploration drilling in Brazil. During the three months ended March 31, 2013, $95 million of exploratory well costs previously capitalized as suspended exploratory well costs for greater than one year at December 31, 2012, were charged to dry hole expense.

Management believes projects with suspended exploratory well costs exhibit sufficient quantities of hydrocarbons to justify potential development and is actively pursuing efforts to assess whether reserves can be attributed to these projects. If additional information becomes available that raises substantial doubt as to the economic or operational viability of any of these projects, the associated costs will be expensed at that time.