Debt - Summary of Long-Term Debt Obligations (Detail) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Current maturities of long-term debt	$ 36	$ 24
Less: unamortized debt issuance costs	(1)
Current maturities of long-term debt, net of unamortized debt issuance costs	35	24
Less: current maturities of long-term debt	(36)	(24)
Less: unamortized debt issuance costs	(141)	(5)
Long-term debt, net of unamortized debt issuance costs	3,397	512
Term Facility [Member]
Debt Instrument [Line Items]
Long-term borrowing	2,249
10.625% Senior Notes [Member]
Debt Instrument [Line Items]
Long-term borrowing	1,300
North Ocean 105 Construction Financing [Member]
Debt Instrument [Line Items]
Long-term borrowing	20	25
Vendor Equipment Financing [Member]
Debt Instrument [Line Items]
Long-term borrowing	$ 5	16
8.000% Second-lien Senior Notes [Member]
Debt Instrument [Line Items]
Long-term borrowing		$ 500

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 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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Amount of long-term debt and capital leases due within one year or the normal operating cycle, if longer.

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