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Debt - Additional Information (Detail) - USD ($)					3 Months Ended	6 Months Ended
Debt - Additional Information (Detail) - USD ($)	May 24, 2019	Oct. 30, 2018	May 10, 2018	Apr. 18, 2018	Jun. 30, 2019	Jun. 30, 2019	Dec. 31, 2018	May 08, 2018
Debt Instrument [Line Items]
Senior secured long-term borrowing								$ 2,260,000,000
Letter of credit facility fee percentage						0.50%
Letter of credit outstanding fronting fee percentage					0.25%	0.25%
Minimum fixed charge coverage ratio						1.50%
Maximum permitted leverage ratio					4.25%	4.25%
Debt instrument covenant minimum liquidity					$ 200,000,000	$ 200,000,000
Future maturities 2019					11,000,000	11,000,000
Future maturities 2020					$ 23,000,000	23,000,000
Amount received under credit facility						1,699,000,000
JRM Mexico [Member]
Debt Instrument [Line Items]
Receivables sold						62,000,000
Factoring costs trade receivables						$ 2,000,000
Percentage of receivables sold withheld and received						10.00%
Cash received from receivables, net of fees and amounts withheld						$ 54,000,000
Fiscal Quarter Ending on or Before September 30, 2019 [Member]
Debt Instrument [Line Items]
Maximum permitted leverage ratio					4.25%	4.25%
Fiscal Quarter Ending December 31, 2019 [Member]
Debt Instrument [Line Items]
Maximum permitted leverage ratio					4.00%	4.00%
Fiscal Quarter Ending After December 31, 2019 and on or Before December 31, 2020 [Member]
Debt Instrument [Line Items]
Maximum permitted leverage ratio					3.75%	3.75%
Fiscal Quarter Ending After December 31, 2020 and on or Before December 31, 2021 [Member]
Debt Instrument [Line Items]
Maximum permitted leverage ratio					3.50%	3.50%
Fiscal Quarter Ending after December 31, 2021 [Member]
Debt Instrument [Line Items]
Maximum permitted leverage ratio					3.25%	3.25%
Interest Rate Swap [Member] \| Designated as Hedging Instrument [Member] \| Cash Flow Hedging [Member]
Debt Instrument [Line Items]
Interest rate derivatives								1,940,000,000
Financial Letters of Credit [Member]
Debt Instrument [Line Items]
Letter of credit participation fee percentage					4.25%	4.25%
Performance Stand By Letters Of Credit [Member]
Debt Instrument [Line Items]
Letter of credit participation fee percentage					2.125%	2.125%
Morgan Stanley Senior Funding Inc
Debt Instrument [Line Items]
Senior secured long-term borrowing	$ 50,000,000
Maximum [Member] \| JRM Mexico [Member]
Debt Instrument [Line Items]
Base rate and applicable margin						2.00%
Maximum [Member] \| Interbank Equilibrium Interest Rate [Member] \| Mexico [Member]
Debt Instrument [Line Items]
Base rate and applicable margin						1.70%
Maximum [Member] \| Financial Letters of Credit [Member]
Debt Instrument [Line Items]
Letter of credit participation fee percentage					4.25%	4.25%
Maximum [Member] \| Performance Stand By Letters Of Credit [Member]
Debt Instrument [Line Items]
Letter of credit participation fee percentage					2.125%	2.125%
Minimum [Member] \| JRM Mexico [Member]
Debt Instrument [Line Items]
Base rate and applicable margin						1.40%
Minimum [Member] \| Interbank Equilibrium Interest Rate [Member] \| Mexico [Member]
Debt Instrument [Line Items]
Base rate and applicable margin						1.40%
Minimum [Member] \| Financial Letters of Credit [Member]
Debt Instrument [Line Items]
Letter of credit participation fee percentage					3.75%	3.75%
Minimum [Member] \| Performance Stand By Letters Of Credit [Member]
Debt Instrument [Line Items]
Letter of credit participation fee percentage					1.875%	1.875%
Letter of Credit Facility [Member]
Debt Instrument [Line Items]
Senior secured long-term borrowing					$ 1,440,000,000	$ 1,440,000,000
Available capacity under credit facility					1,000,000	$ 1,000,000
Facility expire month and year						2023-05
Letters of credit outstanding					1,439,000,000	$ 1,439,000,000
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Senior secured long-term borrowing					1,000,000,000.0	1,000,000,000.0
Available capacity under credit facility					568,000,000	$ 568,000,000
Facility expire month and year						2023-05
Borrowing outstanding					379,000,000	$ 379,000,000
Maximum borrowing outstanding						639,000,000
Letters of credit outstanding					53,000,000	$ 53,000,000
Revolving Credit Facility [Member] \| Eurodollar Rate [Member]
Debt Instrument [Line Items]
Base rate and applicable margin						4.25%
Revolving Credit Facility [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Base rate and applicable margin						3.25%
Revolving Credit Facility [Member] \| Maximum [Member] \| Eurodollar Rate [Member]
Debt Instrument [Line Items]
Base rate and applicable margin						4.25%
Revolving Credit Facility [Member] \| Maximum [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Base rate and applicable margin						3.25%
Revolving Credit Facility [Member] \| Minimum [Member] \| Eurodollar Rate [Member]
Debt Instrument [Line Items]
Base rate and applicable margin						3.75%
Revolving Credit Facility [Member] \| Minimum [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Base rate and applicable margin						2.75%
Financial Letters of Credit [Member]
Debt Instrument [Line Items]
Letters of credit outstanding					49,000,000	$ 49,000,000
Structured Equipment Financing [Member]
Debt Instrument [Line Items]
Available capacity under credit facility					$ 37,000,000	37,000,000
Debt instrument maturity month and year					2020-01
Amount received under credit facility					$ 32,000,000	32,000,000
Term Facility [Member] \| Interest Rate Swap [Member] \| Designated as Hedging Instrument [Member] \| Cash Flow Hedging [Member]
Debt Instrument [Line Items]
Interest rate derivatives								$ 1,940,000,000
Term Facility [Member] \| Eurodollar Rate [Member]
Debt Instrument [Line Items]
Base rate and applicable margin					5.00%
Term Facility [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Base rate and applicable margin					4.00%
Term Facility [Member] \| Floor Rate [Member]
Debt Instrument [Line Items]
Base rate and applicable margin					1.00%
Term Facility [Member]
Debt Instrument [Line Items]
Term facility, borrowings outstanding Amount					$ 2,232,000,000	2,232,000,000	$ 2,243,000,000
Second-lien Notes [Member]
Debt Instrument [Line Items]
Aggregate principal amount redeemed						$ 500,000,000
Debt instrument interest rate						8.00%
Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument interest rate				10.625%
Issue of second-lien seven-year senior secured notes				$ 1,300,000,000
Debt instrument maturity month and year				2024-05
Redemption price percentage				100.00%
Senior Notes [Member] \| One or More Qualified Equity Offerings [Member]
Debt Instrument [Line Items]
Redemption price percentage				110.625%
Senior Notes [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Redemption price percentage				35.00%
Credit Agreement [Member]
Debt Instrument [Line Items]
Senior secured long-term borrowing			$ 4,700,000,000
Credit Agreement [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt instrument mandatory commitment reductions and prepayments subject to reinvestment rights with respect to asset sales			500,000,000
Credit Agreement [Member] \| Letter of Credit Facility [Member]
Debt Instrument [Line Items]
Senior secured long-term borrowing			$ 1,440,000,000
Excess cash flow			75.00%
Decrease in excess cash flow			50.00%
Excess cash flow percentage depending on secured leverage ratio			25.00%
Credit Agreement [Member] \| Term Facility Letters of Credit [Member]
Debt Instrument [Line Items]
Letter of credit facility fee percentage			3.00%
Credit Agreement [Member] \| Term Facility Letters of Credit [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Senior secured long-term borrowing					$ 320,000,000	$ 320,000,000
Credit Agreement [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Senior secured long-term borrowing			$ 1,000,000,000.0
Credit Agreement [Member] \| Revolving Credit Facility [Member] \| Maximum [Member] \| Financial Letters of Credit [Member]
Debt Instrument [Line Items]
Available credit facility for issuance			200,000,000
Credit Agreement [Member] \| Term Facility [Member]
Debt Instrument [Line Items]
Senior secured long-term borrowing			$ 2,260,000,000
Term facility maturity period			7 years
Weighted average interest rate					7.70%	7.70%
Debt instrument periodic payment					$ 5,650,000
Credit Agreement [Member] \| Term Facility [Member] \| Letter of Credit Facility [Member]
Debt Instrument [Line Items]
Debt instrument issued					309,000,000	$ 309,000,000
Available capacity under credit facility					1,000,000	1,000,000
Credit Agreement [Member] \| Term Facility [Member] \| Financial Letters of Credit
Debt Instrument [Line Items]
Debt instrument issued					$ 48,000,000	48,000,000
Credit Agreement [Member] \| Senior Secured Credit Facility [Member] \| Letter of Credit Facility [Member]
Debt Instrument [Line Items]
Deposited cash collateral account to secure reimbursement obligations			$ 319,300,000
Credit Agreement [Member] \| Senior Secured Credit Facility [Member] \| Term Facility Letters of Credit [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Senior secured long-term borrowing			$ 310,000,000.0
Debt Instrument Variable Rate Administrative Agent's Prime Rate [Member] \| Term Facility [Member] \| Eurodollar Rate [Member]
Debt Instrument [Line Items]
Base rate and applicable margin					1.00%
Debt Instrument Variable Rate Administrative Agent's Prime Rate [Member] \| Term Facility [Member] \| Federal Funds Rate [Member]
Debt Instrument [Line Items]
Base rate and applicable margin					0.50%
Letter of Credit Agreement [Member] \| Letter of Credit Facility [Member]
Debt Instrument [Line Items]
Available credit facility for issuance					$ 14,000,000	14,000,000
Debt instrument issued					216,000,000	216,000,000
Available capacity under credit facility		$ 230,000,000
Facility expire month and year		2021-12
North Ocean Construction Financing [Member]
Debt Instrument [Line Items]
Term facility, borrowings outstanding Amount					12,000,000	12,000,000	$ 16,000,000
North Ocean Construction Financing [Member] \| Secured Debt [Member] \| North Ocean 105 [Member]
Debt Instrument [Line Items]
Term facility, borrowings outstanding Amount					12,000,000	12,000,000
Future maturities 2019					4,000,000	4,000,000
Future maturities 2020					$ 8,000,000	$ 8,000,000