Debt - Summary of Long-Term Debt Obligations (Detail) - USD ($) $ in Millions	Jun. 30, 2018	May 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Current maturities of long-term debt	$ 43		$ 24
Less: unamortized debt issuance costs	(1)
Current maturities of long-term debt, net of unamortized debt issuance costs	42		24
Capital lease	22	$ 21	1
Less: current maturities of long-term debt	(43)		(24)
Less: unamortized debt issuance costs	(146)		(5)
Long-term debt, net of unamortized debt issuance costs	3,418		513
Term Facility [Member]
Debt Instrument [Line Items]
Long-term borrowing	2,254
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	21		25
Vendor Equipment Financing [Member]
Debt Instrument [Line Items]
Long-term borrowing	$ 10		16
8.000% Second-lien Senior Notes [Member]
Debt Instrument [Line Items]
Long-term borrowing			$ 500