Debt - Summary of Long-Term Debt Obligations (Detail) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Revolving credit facility	$ 801
Less: unamortized debt issuance costs		$ (1)
Current debt, net of unamortized debt issuance costs	4,306	30
Less: current maturities of long-term debt	(4,306)	(30)
Less: unamortized debt issuance costs		(136)
Long-term debt, net of unamortized debt issuance costs		3,393
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Revolving credit facility	801
Structured Equipment Financing [Member]
Debt Instrument [Line Items]
Revolving credit facility	32
New Term Facility [Member]
Debt Instrument [Line Items]
Long-term borrowing current	746
Term Facility [Member]
Debt Instrument [Line Items]
Long-term borrowing current	2,220	23
Long-term borrowing	2,200	2,243
10.625% Senior Notes [Member]
Debt Instrument [Line Items]
Long-term borrowing current	1,300
Long-term borrowing		1,300
North Ocean 105 Construction Financing [Member]
Debt Instrument [Line Items]
Long-term borrowing current	$ 8	8
Long-term borrowing		$ 16

Long term debt and capital lease obligations current net.

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Long term debt and capital lease obligations net.

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Amount, after accumulated amortization, of debt issuance costs classified as current. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount, after accumulated amortization, of debt issuance costs classified as noncurrent. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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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.

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

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