Details Of Certain Accounts (Accrued Liabilities) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Details Of Certain Accounts [Abstract]
Accrued payroll and related benefits	$ 61,246	$ 50,527
Current asset retirement obligations	575	2,024
Unearned revenue	11,461us-gaap_DeferredRevenueCurrent	19,608us-gaap_DeferredRevenueCurrent
Billing in excess of cost		1,677us-gaap_BillingsInExcessOfCostCurrent
Accrued interest	4,221us-gaap_InterestPayableCurrent	4,187us-gaap_InterestPayableCurrent
Derivative liability (Note 15)	13,222us-gaap_HedgingLiabilitiesCurrent	2,651us-gaap_HedgingLiabilitiesCurrent
Taxes payable excluding income tax payable	6,236us-gaap_TaxesPayableCurrent	4,811us-gaap_TaxesPayableCurrent
Pipelay assets sale deposit		5,000us-gaap_DepositLiabilityCurrent
Other	7,962us-gaap_OtherAccruedLiabilitiesCurrent	5,997us-gaap_OtherAccruedLiabilitiesCurrent
Total accrued liabilities	$ 104,923us-gaap_AccruedLiabilitiesCurrent	$ 96,482us-gaap_AccruedLiabilitiesCurrent

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Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Current portion of the carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

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Liability attributable to (i) billings in excess of costs under the percentage of completion contract accounting method representing the difference between contractually invoiced amounts (billings) and revenue recognized based, for example, on costs incurred to estimated total costs at period end or (ii) contractually invoiced amounts (billings) in excess of costs incurred and accumulated under the completed contract accounting method that are expected to be realized within one year or one operating cycle, whichever is longer, from the reporting date.

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The carrying amount of consideration received or receivable as of the balance sheet date on potential earnings that were not recognized as revenue in conformity with GAAP, and which are expected to be recognized as such within one year or the normal operating cycle, if longer, including sales, license fees, and royalties, but excluding interest income.

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The current portion, due within one year or one operating cycle, if longer, of deposits held other than customer deposits.

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Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying amount as of the balance sheet date of the liability arising from a financial instrument or a contract used to mitigate a specified risk (hedge), and which are expected to be converted into cash or otherwise disposed of within a year or the normal operating cycle, if longer.

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Carrying value as of the balance sheet date of [accrued] interest payable on all forms of debt, including trade payables, that has been incurred and is unpaid. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations incurred through that date and payable arising from transactions not otherwise specified in the taxonomy. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations incurred and payable for statutory income, sales, use, payroll, excise, real, property and other taxes. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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