Contingencies	3 Months Ended
Jun. 30, 2011
Contingencies [Abstract]
Contingencies	13. Contingencies In 2007, Schlumberger received an inquiry from the United States Department of Justice (“DOJ”) related to the DOJ’s investigation of whether certain freight forwarding and customs clearance services of Panalpina, Inc., and other companies provided to oil and oilfield service companies, including Schlumberger, violated the Foreign Corrupt Practices Act. Schlumberger is cooperating with the governmental authorities and is currently unable to predict the outcome of this matter. In 2009, Schlumberger learned that United States officials began a grand jury investigation and an associated regulatory inquiry, both related to certain Schlumberger operations in specified countries that are subject to United States trade and economic sanctions. Also in 2009, Smith received an administrative subpoena with respect to its historical business practices in certain countries that are subject to United States trade and economic sanctions. Schlumberger is cooperating with the governmental authorities and is currently unable to predict the outcome of these matters. On April 20, 2010, a fire and explosion occurred onboard the semisubmersible drilling rig Deepwater Horizon, owned by Transocean Ltd. and under contract to a subsidiary of BP plc. Pursuant to a contract between M-I SWACO and BP, M-I SWACO provided certain services under the direction of BP. A number of legal actions, certain of which name an M-I SWACO entity as a defendant, have been filed in connection with the Deepwater Horizon incident, and additional legal actions may be filed in the future. Based on information currently known, the amount of any potential loss attributable to M-I SWACO with respect to potential liabilities related to the incident would not be material to Schlumberger’s consolidated financial position. Schlumberger and its subsidiaries are party to various other legal proceedings from time to time. A liability is accrued when a loss is both probable and can be reasonably estimated. Management believes that the probability of a material loss is remote and, as such, that any liability that might ensue would not be material in relation to Schlumberger’s consolidated financial position. However, litigation is inherently uncertain and it is not possible to predict the ultimate disposition of these proceedings.

Contingencies

3 Months Ended

Jun. 30, 2011

13. Contingencies

In 2007, Schlumberger received an inquiry from the United States Department of Justice (“DOJ”) related to the DOJ’s investigation of whether certain freight forwarding and customs clearance services of Panalpina, Inc., and other companies provided to oil and oilfield service companies, including Schlumberger, violated the Foreign Corrupt Practices Act. Schlumberger is cooperating with the governmental authorities and is currently unable to predict the outcome of this matter.

In 2009, Schlumberger learned that United States officials began a grand jury investigation and an associated regulatory inquiry, both related to certain Schlumberger operations in specified countries that are subject to United States trade and economic sanctions. Also in 2009, Smith received an administrative subpoena with respect to its historical business practices in certain countries that are subject to United States trade and economic sanctions. Schlumberger is cooperating with the governmental authorities and is currently unable to predict the outcome of these matters.

On April 20, 2010, a fire and explosion occurred onboard the semisubmersible drilling rig Deepwater Horizon, owned by Transocean Ltd. and under contract to a subsidiary of BP plc. Pursuant to a contract between M-I SWACO and BP, M-I SWACO provided certain services under the direction of BP. A number of legal actions, certain of which name an M-I SWACO entity as a defendant, have been filed in connection with the Deepwater Horizon incident, and additional legal actions may be filed in the future. Based on information currently known, the amount of any potential loss attributable to M-I SWACO with respect to potential liabilities related to the incident would not be material to Schlumberger’s consolidated financial position.

Schlumberger and its subsidiaries are party to various other legal proceedings from time to time. A liability is accrued when a loss is both probable and can be reasonably estimated. Management believes that the probability of a material loss is remote and, as such, that any liability that might ensue would not be material in relation to Schlumberger’s consolidated financial position. However, litigation is inherently uncertain and it is not possible to predict the ultimate disposition of these proceedings.