Contingencies	6 Months Ended
Jun. 30, 2015
Commitments and Contingencies Disclosure [Abstract]
Contingencies	Contingencies Brazil Internal Investigation Pride International, Inc. (“Pride”) commenced drilling operations in Brazil during 2001, and, in 2008, entered into a drilling contract with Petrobras for DS-5, a rig Pride had ordered from a shipyard in South Korea. At the time Ensco acquired Pride in mid-2011, Pride’s Brazil fleet had grown to ten rigs. Beginning in 2006, Pride conducted periodic compliance reviews of its business with Petrobras, and, after the acquisition, Ensco conducted similar compliance reviews, the most recent of which commenced after media reports surfaced regarding ongoing investigations of various kickback and bribery schemes in Brazil. While conducting our most recent compliance review, we became aware of an internal audit report prepared by Petrobras, after media reports surfaced regarding its contents. The audit report alleges irregularities in relation to DS-5 - specifically, that Petrobras overpaid under the DS-5 drilling contract, purportedly because the terms of the DS-5 contract were more favorable to Pride than the terms that Petrobras had negotiated with other offshore drilling contractors during that time. We believe this allegation by Petrobras is inaccurate, as publicly available data show that the DS-5 contract terms were comparable to other contracts signed by Petrobras in late 2007 and early 2008. We have provided this information to Petrobras as relevant to their internal audit report. Petrobras submitted its internal audit report to Brazilian governmental authorities, who have subsequently requested a copy of the DS-5 drilling contract from Petrobras. Statements from the internal audit report, including those relating to alleged overpayments for the DS-5 contract, were subsequently cited along with other allegations in Brazilian court procedural documents used in the arrest of a former Petrobras director. While the Petrobras internal audit report became public more than two months ago, we have not been contacted by Brazil authorities. Nevertheless, upon learning of the Petrobras internal audit report, our Audit Committee expanded the scope of our most recent review of our business with Petrobras. Also, our Audit Committee appointed independent counsel to commission and undertake an internal investigation to examine the facts and circumstances surrounding the allegations set forth in the internal audit report and court documents related to the arrest of the former Petrobras director. Our investigation is ongoing, but to date we have found no evidence that Pride was involved in any wrongdoing. Our rigs working for Petrobras continue to operate under their existing contracts. Further, we have voluntarily contacted the SEC and the U.S. Department of Justice (“DOJ”) to advise them of the internal audit report and our Audit Committee’s independent investigation. We cannot predict whether any governmental authority will seek to investigate this matter, or if a proceeding were opened, the scope or ultimate outcome of any such investigation. If the SEC or DOJ determines that violations of the U.S. Foreign Corrupt Practices Act of 1977 (the "FCPA") have occurred, or if any governmental authority determines that we have violated applicable anti-bribery laws, they could seek civil and criminal sanctions, including monetary penalties, against us, as well as changes to our business practices and compliance programs, any of which could have a material adverse effect on our business and financial condition. ENSCO 74 Loss During 2008, ENSCO 74 was lost as a result of Hurricane Ike in the U.S. Gulf of Mexico. The ENSCO 74 sunken rig hull was located approximately 95 miles from the original drilling location when it was struck by an oil tanker during 2009. Wreck removal operations on the sunken rig hull of ENSCO 74 were completed during 2010. We filed a petition for exoneration or limitation of liability under U.S. admiralty and maritime law during 2009. A number of claimants presented claims in the exoneration/limitation proceedings. We have liability insurance policies that provide coverage for such claims as well as removal of wreckage and debris in excess of the property insurance policy sublimit, subject to a $10.0 million per occurrence deductible for third-party claims and an annual aggregate limit of $490.0 million. The owner of a pipeline filed claims alleging that ENSCO 74 caused the pipeline to rupture during Hurricane Ike and sought damages for the cost of repairs and business interruption in an amount in excess of $26.0 million. During 2014, we reached an agreement with the owner of the pipeline to settle the claims for $9.6 million. Prior to the settlement, we incurred legal fees of $3.6 million for this matter. During the second quarter of 2014, we paid the remaining $6.4 million of our deductible under our liability insurance policy. The remaining $3.2 million of settlement proceeds was paid by our underwriters under the terms of the related insurance policies. The owner of the oil tanker that struck the hull of ENSCO 74 filed claims seeking monetary damages currently in excess of $5.0 million for losses incurred when the tanker struck the ENSCO 74 hull. This matter went to trial in June 2014, and we won a directed verdict on all claims. The plaintiff appealed the decision to the United States Court of Appeals for the Fifth Circuit. We believe that it is not probable that a liability exists with respect to these claims. We believe all liabilities associated with the ENSCO 74 loss during Hurricane Ike resulted from a single occurrence under the terms of the applicable insurance policies. However, legal counsel for certain liability underwriters have asserted that the liability claims arise from separate occurrences. In the event of multiple occurrences, the self-insured retention is $15.0 million for two occurrences and $1.0 million for each occurrence thereafter. Although we do not expect final disposition of the claims associated with the ENSCO 74 loss to have a material adverse effect upon our financial position, operating results or cash flows, there can be no assurances as to the ultimate outcome. ENSCO 29 Wreck Removal During 2005, a portion of the ENSCO 29 platform drilling rig was lost over the side of a customer's platform as a result of Hurricane Katrina. In June 2014, we received a letter from an operator demanding that Ensco retrieve the derrick and drawworks from the seabed. Our property insurance policies include coverage for ENSCO 29 wreckage and debris removal costs up to $3.8 million. We also maintain liability insurance policies that provide coverage under certain circumstances for wreckage and debris removal costs in excess of the $3.8 million coverage provided under the property insurance policies. We believe that it is not probable a liability exists with respect to this matter, and no liability has been recorded on our condensed consolidated balance sheet as of June 30, 2015. While we cannot reasonably estimate a range of possible loss at this time, it is possible that removal costs may be in excess of our insurance coverage. Although we do not expect costs associated with the ENSCO 29 wreck removal to have a material adverse effect upon our financial position, operating results or cash flows, there can be no assurances as to the ultimate outcome. Asbestos Litigation We and certain subsidiaries have been named as defendants, along with numerous third-party companies as co-defendants, in multi-party lawsuits filed in Illinois, Mississippi, Texas, Louisiana and the U.K. by approximately 65 plaintiffs. The lawsuits seek an unspecified amount of monetary damages on behalf of individuals alleging personal injury or death, primarily under the Jones Act, purportedly resulting from exposure to asbestos on drilling rigs and associated facilities during the 1960s through the 1980s. During 2013, we reached an agreement in principle with 58 plaintiffs to settle lawsuits filed in Mississippi for a nominal amount. A special master reviewed all 58 cases and made an allocation of settlement funds among the parties. The District Court Judge reviewed the allocations and accepted the special master’s recommendations and approved the settlements. The settlement documents and final documentation for the individual plaintiffs are continuing to be processed. We intend to vigorously defend against the remaining claims and have filed responsive pleadings preserving all defenses and challenges to jurisdiction and venue. However, discovery is still ongoing and, therefore, available information regarding the nature of all pending claims is limited. At present, we cannot reasonably determine how many of the claimants may have valid claims under the Jones Act or estimate a range of potential liability exposure, if any. In addition to the pending cases in Illinois, Mississippi, Texas, Louisiana and the U.K., we have other asbestos or lung injury claims pending against us in litigation in other jurisdictions. Although we do not expect final disposition of these asbestos or lung injury lawsuits to have a material adverse effect upon our financial position, operating results or cash flows, there can be no assurances as to the ultimate outcome of the lawsuits. Other Matters In addition to the foregoing, we are named defendants or parties in certain other lawsuits, claims or proceedings incidental to our business and are involved from time to time as parties to governmental investigations or proceedings, including matters related to taxation, arising in the ordinary course of business. Although the outcome of such lawsuits or other proceedings cannot be predicted with certainty and the amount of any liability that could arise with respect to such lawsuits or other proceedings cannot be predicted accurately, we do not expect these matters to have a material adverse effect on our financial position, operating results or cash flows. In the ordinary course of business with customers and others, we have entered into letters of credit and surety bonds to guarantee our performance as it relates to our drilling contracts, contract bidding, customs duties, tax appeals and other obligations in various jurisdictions. Letters of credit and surety bonds outstanding as of June 30, 2015 totaled $229.6 million and were issued under facilities provided by various banks and other financial institutions. Obligations under these letters of credit and surety bonds are not normally called as we typically comply with the underlying performance requirement. As of June 30, 2015, we had not been required to make collateral deposits with respect to these agreements.

Contingencies

Brazil Internal Investigation

Pride International, Inc. (“Pride”) commenced drilling operations in Brazil during 2001, and, in 2008, entered into a drilling contract with Petrobras for DS-5, a rig Pride had ordered from a shipyard in South Korea. At the time Ensco acquired Pride in mid-2011, Pride’s Brazil fleet had grown to ten rigs.

Beginning in 2006, Pride conducted periodic compliance reviews of its business with Petrobras, and, after the acquisition, Ensco conducted similar compliance reviews, the most recent of which commenced after media reports surfaced regarding ongoing investigations of various kickback and bribery schemes in Brazil.

While conducting our most recent compliance review, we became aware of an internal audit report prepared by Petrobras, after media reports surfaced regarding its contents. The audit report alleges irregularities in relation to DS-5 - specifically, that Petrobras overpaid under the DS-5 drilling contract, purportedly because the terms of the DS-5 contract were more favorable to Pride than the terms that Petrobras had negotiated with other offshore drilling contractors during that time. We believe this allegation by Petrobras is inaccurate, as publicly available data show that the DS-5 contract terms were comparable to other contracts signed by Petrobras in late 2007 and early 2008. We have provided this information to Petrobras as relevant to their internal audit report. Petrobras submitted its internal audit report to Brazilian governmental authorities, who have subsequently requested a copy of the DS-5 drilling contract from Petrobras.

Statements from the internal audit report, including those relating to alleged overpayments for the DS-5 contract, were subsequently cited along with other allegations in Brazilian court procedural documents used in the arrest of a former Petrobras director. While the Petrobras internal audit report became public more than two months ago, we have not been contacted by Brazil authorities.

Nevertheless, upon learning of the Petrobras internal audit report, our Audit Committee expanded the scope of our most recent review of our business with Petrobras. Also, our Audit Committee appointed independent counsel to commission and undertake an internal investigation to examine the facts and circumstances surrounding the allegations set forth in the internal audit report and court documents related to the arrest of the former Petrobras director. Our investigation is ongoing, but to date we have found no evidence that Pride was involved in any wrongdoing.

Our rigs working for Petrobras continue to operate under their existing contracts. Further, we have voluntarily contacted the SEC and the U.S. Department of Justice (“DOJ”) to advise them of the internal audit report and our Audit Committee’s independent investigation. We cannot predict whether any governmental authority will seek to investigate this matter, or if a proceeding were opened, the scope or ultimate outcome of any such investigation. If the SEC or DOJ determines that violations of the U.S. Foreign Corrupt Practices Act of 1977 (the "FCPA") have occurred, or if any governmental authority determines that we have violated applicable anti-bribery laws, they could seek civil and criminal sanctions, including monetary penalties, against us, as well as changes to our business practices and compliance programs, any of which could have a material adverse effect on our business and financial condition.

ENSCO 74 Loss

During 2008, ENSCO 74 was lost as a result of Hurricane Ike in the U.S. Gulf of Mexico. The ENSCO 74 sunken rig hull was located approximately 95 miles from the original drilling location when it was struck by an oil tanker during 2009. Wreck removal operations on the sunken rig hull of ENSCO 74 were completed during 2010.

We filed a petition for exoneration or limitation of liability under U.S. admiralty and maritime law during 2009. A number of claimants presented claims in the exoneration/limitation proceedings. We have liability insurance policies that provide coverage for such claims as well as removal of wreckage and debris in excess of the property insurance policy sublimit, subject to a $10.0 million per occurrence deductible for third-party claims and an annual aggregate limit of $490.0 million.

The owner of a pipeline filed claims alleging that ENSCO 74 caused the pipeline to rupture during Hurricane Ike and sought damages for the cost of repairs and business interruption in an amount in excess of $26.0 million. During 2014, we reached an agreement with the owner of the pipeline to settle the claims for $9.6 million. Prior to the settlement, we incurred legal fees of $3.6 million for this matter. During the second quarter of 2014, we paid the remaining $6.4 million of our deductible under our liability insurance policy. The remaining $3.2 million of settlement proceeds was paid by our underwriters under the terms of the related insurance policies.

The owner of the oil tanker that struck the hull of ENSCO 74 filed claims seeking monetary damages currently in excess of $5.0 million for losses incurred when the tanker struck the ENSCO 74 hull. This matter went to trial in June 2014, and we won a directed verdict on all claims. The plaintiff appealed the decision to the United States Court of Appeals for the Fifth Circuit. We believe that it is not probable that a liability exists with respect to these claims.

We believe all liabilities associated with the ENSCO 74 loss during Hurricane Ike resulted from a single occurrence under the terms of the applicable insurance policies. However, legal counsel for certain liability underwriters have asserted that the liability claims arise from separate occurrences. In the event of multiple occurrences, the self-insured retention is $15.0 million for two occurrences and $1.0 million for each occurrence thereafter.

Although we do not expect final disposition of the claims associated with the ENSCO 74 loss to have a material adverse effect upon our financial position, operating results or cash flows, there can be no assurances as to the ultimate outcome.

ENSCO 29 Wreck Removal

During 2005, a portion of the ENSCO 29 platform drilling rig was lost over the side of a customer's platform as a result of Hurricane Katrina. In June 2014, we received a letter from an operator demanding that Ensco retrieve the derrick and drawworks from the seabed.

Our property insurance policies include coverage for ENSCO 29 wreckage and debris removal costs up to $3.8 million. We also maintain liability insurance policies that provide coverage under certain circumstances for wreckage and debris removal costs in excess of the $3.8 million coverage provided under the property insurance policies. We believe that it is not probable a liability exists with respect to this matter, and no liability has been recorded on our condensed consolidated balance sheet as of June 30, 2015. While we cannot reasonably estimate a range of possible loss at this time, it is possible that removal costs may be in excess of our insurance coverage. Although we do not expect costs associated with the ENSCO 29 wreck removal to have a material adverse effect upon our financial position, operating results or cash flows, there can be no assurances as to the ultimate outcome.

Asbestos Litigation

We and certain subsidiaries have been named as defendants, along with numerous third-party companies as co-defendants, in multi-party lawsuits filed in Illinois, Mississippi, Texas, Louisiana and the U.K. by approximately 65 plaintiffs. The lawsuits seek an unspecified amount of monetary damages on behalf of individuals alleging personal injury or death, primarily under the Jones Act, purportedly resulting from exposure to asbestos on drilling rigs and associated facilities during the 1960s through the 1980s.

During 2013, we reached an agreement in principle with 58 plaintiffs to settle lawsuits filed in Mississippi for a nominal amount. A special master reviewed all 58 cases and made an allocation of settlement funds among the parties. The District Court Judge reviewed the allocations and accepted the special master’s recommendations and approved the settlements. The settlement documents and final documentation for the individual plaintiffs are continuing to be processed.

We intend to vigorously defend against the remaining claims and have filed responsive pleadings preserving all defenses and challenges to jurisdiction and venue. However, discovery is still ongoing and, therefore, available information regarding the nature of all pending claims is limited. At present, we cannot reasonably determine how many of the claimants may have valid claims under the Jones Act or estimate a range of potential liability exposure, if any.

In addition to the pending cases in Illinois, Mississippi, Texas, Louisiana and the U.K., we have other asbestos or lung injury claims pending against us in litigation in other jurisdictions. Although we do not expect final disposition of these asbestos or lung injury lawsuits to have a material adverse effect upon our financial position, operating results or cash flows, there can be no assurances as to the ultimate outcome of the lawsuits.

Other Matters

In addition to the foregoing, we are named defendants or parties in certain other lawsuits, claims or proceedings incidental to our business and are involved from time to time as parties to governmental investigations or proceedings, including matters related to taxation, arising in the ordinary course of business. Although the outcome of such lawsuits or other proceedings cannot be predicted with certainty and the amount of any liability that could arise with respect to such lawsuits or other proceedings cannot be predicted accurately, we do not expect these matters to have a material adverse effect on our financial position, operating results or cash flows.

In the ordinary course of business with customers and others, we have entered into letters of credit and surety bonds to guarantee our performance as it relates to our drilling contracts, contract bidding, customs duties, tax appeals and other obligations in various jurisdictions. Letters of credit and surety bonds outstanding as of June 30, 2015 totaled $229.6 million and were issued under facilities provided by various banks and other financial institutions. Obligations under these letters of credit and surety bonds are not normally called as we typically comply with the underlying performance requirement. As of June 30, 2015, we had not been required to make collateral deposits with respect to these agreements.