Debt - Summary of Carrying Values Debt Obligations (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Debtor-in-Possession Term Facility	$ 2,032
Debt	2,038	$ 5,107
New Term Facility [Member]
Debt Instrument [Line Items]
Long-term borrowing current		800
Discount on New Term Facility	(37)	(54)
Term Facility [Member]
Debt Instrument [Line Items]
Long-term borrowing current		2,220
North Ocean 105 Construction Financing [Member]
Debt Instrument [Line Items]
Long-term borrowing current	8	8
10.625% Senior Notes [Member]
Debt Instrument [Line Items]
Long-term borrowing current		1,300
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Structured equipment financing		801
Structured Equipment Financing [Member]
Debt Instrument [Line Items]
Structured equipment financing	$ 35	$ 32

Long term debt and capital lease obligations current net.

No definition available.

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- Definition

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.

+ References

No definition available.

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- Definition

Amount of debt discount to be amortized within one year or within the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28541-108399

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

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- Definition

Amount debtor-in-possession financing arranged (but not necessarily all borrowed).

+ References

No definition available.

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- Definition

The carrying value as of the balance sheet date of the current portion 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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(13))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-SubTopic 10
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