Indebtedness - Bank Loan Agreement - Additional Information (Detail) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
May 31, 2015	Mar. 31, 2017
Debt [Line Items]
Covenant compliance description		At March 31, 2017, the company failed to meet certain covenants contained in the Bank Loan Agreement, the Troms Offshore Debt agreement, and the September 2013 Senior Notes, which resulted in covenant noncompliance that would have allowed the respective lenders and/or the noteholders to declare us to be in default under each of the Funded Debt Agreements, and accelerate the indebtedness thereunder. To avoid an acceleration of indebtedness of these agreements (and potentially the August 2011 and September 2010 Senior Notes) the company negotiated and obtained limited waivers from the necessary lenders and noteholders. When the final waiver expired in accordance with its terms on April 7, 2017, negotiations regarding the terms of the company’s restructuring were substantially complete. As a result of the above, all of the company’s debt was classified as current on its Consolidated Balance Sheet at March 31, 2017.
Current Bank Loan Agreement
Debt [Line Items]
Bank loan agreement expiration date	2019-06
Revolving credit facility	$ 900
Credit facility term	5 years
Revolving line of credit	$ 600
Term loan	$ 300
Term Loan Facility
Debt [Line Items]
Outstanding borrowing		$ 300
Estimated fair market value of the borrowing		168
Revolving Credit Agreement
Debt [Line Items]
Outstanding borrowing		600
Estimated fair market value of the borrowing		$ 336

Line Of Credit Estimated Fair Market Value

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Line of Credit Facility Expiration Dates

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Line Of Credit Facility Revolving Line Of Credit

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Line Of Credit Facility Term Loan

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States whether the entity was in compliance with the debt covenants throughout the reporting period, and describes facts and circumstances of any compliance failure.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Period remaining on line of credit facility before it terminates, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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