Commitments And Contingencies And Other Matters	6 Months Ended
Jun. 30, 2017
Commitments and Contingencies Disclosure [Abstract]
Commitments And Contingencies And Other Matters	Commitments and Contingencies and Other Matters Commitments We have charter agreements for the Grand Canyon, Grand Canyon II and Grand Canyon III vessels for use in our robotics operations. In February 2016, we amended the charter agreements to reduce the charter rates and, in connection with those reductions, to extend the terms to October 2019 for the Grand Canyon, to April 2021 for the Grand Canyon II and to May 2023 for the Grand Canyon III. We also have a charter agreement for the Deep Cygnus that expires in March 2018. In September 2013, we executed a contract with the same shipyard in Singapore that constructed the Q5000 for the construction of a newbuild semi-submersible well intervention vessel, the Q7000, which is being built to North Sea standards. This $346.0 million shipyard contract represents the majority of the expected costs associated with the construction of the Q7000. Pursuant to the original contract and subsequent amendments, 20% of the contract price was paid upon the signing of the contract in 2013, 20% was paid in 2016, 20% is to be paid upon issuance of the Completion Certificate, which is to be issued on or before December 31, 2017, and 40% is to be paid upon the delivery of the vessel, which at our option can be deferred until December 30, 2018. We agreed to pay the shipyard its incremental costs in connection with the contract amendments to extend the scheduled delivery of the Q7000 and to defer certain payment obligations. Incremental costs are capitalized as they are incurred during the construction of the vessel. At June 30, 2017, our total investment in the Q7000 was $207.1 million, including $138.4 million of installment payments to the shipyard. In February 2014, we entered into agreements with Petróleo Brasileiro S.A. (“Petrobras”) to provide well intervention services offshore Brazil, and in connection with the Petrobras agreements, we entered into charter agreements with Siem Offshore AS (“Siem”) for two newbuild monohull vessels, the Siem Helix 1 and the Siem Helix 2. The initial term of the charter agreements with Siem is for seven years from the respective vessel delivery dates with options to extend. The initial term of the agreements with Petrobras is for four years with Petrobras’s options to extend. As part of Petrobras’s efforts to reduce its costs structure with many of its suppliers, we and Petrobras began discussions in mid-2015 with respect to potentially amending our contracts in a manner that would address Petrobras’s objectives and was acceptable to us as well. Those negotiations were finalized in early June 2016 such that the contracts for the Siem Helix 1, originally scheduled to begin no later than July 22, 2016, were amended to commence between July 22, 2016 and October 21, 2016, with the day rate reduced to a mutually acceptable level, and the contracts for the Siem Helix 2, originally scheduled to begin no later than January 21, 2017, were amended to commence between October 1, 2017 and December 31, 2017, with no change in the day rate. The Siem Helix 1 vessel was delivered to us and the charter term began on June 14, 2016 and, after integration of our topside equipment onboard, transited to Brazil. After a prolonged inspection and acceptance process, the vessel was accepted by Petrobras and commenced operations on April 14, 2017. We have agreed with Petrobras to commence operations at reduced day rates as we work through certain items identified in the vessel acceptance process. The Siem Helix 2 was delivered to us and the charter term began on February 10, 2017. We are currently integrating and commissioning our topside equipment onboard the vessel, and we anticipate that the vessel will commence operations for Petrobras late in the fourth quarter of 2017. At June 30, 2017, our total investment in the topside equipment for the two vessels was $275.0 million. Contingencies and Claims We believe that there are currently no contingencies that would have a material adverse effect on our financial position, results of operations or cash flows. Litigation We are involved in various other legal proceedings, some involving claims for personal injury under the General Maritime Laws of the United States and the Jones Act based on alleged negligence. In addition, from time to time we incur other claims, such as contract and employment-related disputes, in the normal course of business.

Commitments and Contingencies and Other Matters

Commitments

We have charter agreements for the Grand Canyon, Grand Canyon II and Grand Canyon III vessels for use in our robotics operations. In February 2016, we amended the charter agreements to reduce the charter rates and, in connection with those reductions, to extend the terms to October 2019 for the Grand Canyon, to April 2021 for the Grand Canyon II and to May 2023 for the Grand Canyon III. We also have a charter agreement for the Deep Cygnus that expires in March 2018.

In September 2013, we executed a contract with the same shipyard in Singapore that constructed the Q5000 for the construction of a newbuild semi-submersible well intervention vessel, the Q7000, which is being built to North Sea standards. This $346.0 million shipyard contract represents the majority of the expected costs associated with the construction of the Q7000. Pursuant to the original contract and subsequent amendments, 20% of the contract price was paid upon the signing of the contract in 2013, 20% was paid in 2016, 20% is to be paid upon issuance of the Completion Certificate, which is to be issued on or before December 31, 2017, and 40% is to be paid upon the delivery of the vessel, which at our option can be deferred until December 30, 2018. We agreed to pay the shipyard its incremental costs in connection with the contract amendments to extend the scheduled delivery of the Q7000 and to defer certain payment obligations. Incremental costs are capitalized as they are incurred during the construction of the vessel. At June 30, 2017, our total investment in the Q7000 was $207.1 million, including $138.4 million of installment payments to the shipyard.

In February 2014, we entered into agreements with Petróleo Brasileiro S.A. (“Petrobras”) to provide well intervention services offshore Brazil, and in connection with the Petrobras agreements, we entered into charter agreements with Siem Offshore AS (“Siem”) for two newbuild monohull vessels, the Siem Helix 1 and the Siem Helix 2. The initial term of the charter agreements with Siem is for seven years from the respective vessel delivery dates with options to extend. The initial term of the agreements with Petrobras is for four years with Petrobras’s options to extend. As part of Petrobras’s efforts to reduce its costs structure with many of its suppliers, we and Petrobras began discussions in mid-2015 with respect to potentially amending our contracts in a manner that would address Petrobras’s objectives and was acceptable to us as well. Those negotiations were finalized in early June 2016 such that the contracts for the Siem Helix 1, originally scheduled to begin no later than July 22, 2016, were amended to commence between July 22, 2016 and October 21, 2016, with the day rate reduced to a mutually acceptable level, and the contracts for the Siem Helix 2, originally scheduled to begin no later than January 21, 2017, were amended to commence between October 1, 2017 and December 31, 2017, with no change in the day rate.

The Siem Helix 1 vessel was delivered to us and the charter term began on June 14, 2016 and, after integration of our topside equipment onboard, transited to Brazil. After a prolonged inspection and acceptance process, the vessel was accepted by Petrobras and commenced operations on April 14, 2017. We have agreed with Petrobras to commence operations at reduced day rates as we work through certain items identified in the vessel acceptance process. The Siem Helix 2 was delivered to us and the charter term began on February 10, 2017. We are currently integrating and commissioning our topside equipment onboard the vessel, and we anticipate that the vessel will commence operations for Petrobras late in the fourth quarter of 2017. At June 30, 2017, our total investment in the topside equipment for the two vessels was $275.0 million.

Contingencies and Claims

We believe that there are currently no contingencies that would have a material adverse effect on our financial position, results of operations or cash flows.

Litigation

We are involved in various other legal proceedings, some involving claims for personal injury under the General Maritime Laws of the United States and the Jones Act based on alleged negligence. In addition, from time to time we incur other claims, such as contract and employment-related disputes, in the normal course of business.