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-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3213-108585

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Carrying amount of collateralized debt obligations with maturities initially due after one year or beyond the operating cycle, if longer, excluding the current portion. Obligations include, but not limited to, mortgage loans, chattel loans, and other borrowings secured by assets.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.8)
-URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227

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Debt - Additional Information (Detail)				1 Months Ended	3 Months Ended			9 Months Ended
Debt - Additional Information (Detail)	May 10, 2018 USD ($)	Apr. 18, 2018 USD ($)	Sep. 30, 2010 USD ($) Installment	Feb. 28, 2017 USD ($)	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Sep. 30, 2018 USD ($)	May 08, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 18, 2017
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
Percentage of interest acquired in subsidiary											53.00%
Future maturities remainder of 2018					6,000,000			6,000,000
Future maturities 2019					23,000,000			23,000,000
Future maturities 2020					23,000,000			23,000,000
JRM Mexico [Member]
Debt Instrument [Line Items]
Receivables sold								179,000,000
Factoring costs trade receivables					1,000,000			$ 3,000,000
Percentage of receivables sold withheld and received								10.00%
Cash received from receivables, net of fees and amounts withheld								$ 159,000,000
Loan agreement for equipment financing, term				21 months
Equipment financing amount				$ 47,000,000
Debt instrument, interest rate				5.75%
Borrowing outstanding					$ 5,000,000			$ 5,000,000
McDermott International Management [Member]
Debt Instrument [Line Items]
Description of loan agreement								JRM Mexico’s obligations in connection with this equipment financing are guaranteed by McDermott International Management, S. de RL., one of our indirect, wholly owned subsidiaries
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%
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								1.90%
Minimum [Member] \| Interbank Equilibrium Interest Rate [Member] \| Mexico [Member]
Debt Instrument [Line Items]
Base rate and applicable margin								1.50%
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					$ 1,390,000,000			$ 1,390,000,000
Available capacity under credit facility					14,000,000,000			$ 14,000,000,000
Facility expire month and year								2023-05
Letters of credit outstanding					1,376,000,000			$ 1,376,000,000
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Senior secured long-term borrowing					1,000,000,000			1,000,000,000
Available capacity under credit facility					858,000,000			$ 858,000,000
Facility expire month and year								2023-05
Letters of credit outstanding					14,000,000			$ 14,000,000
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					48,400,000			$ 48,400,000
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					$ 2,249,000,000			$ 2,249,000,000
Term facility maturity period					7 years			7 years
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	$ 4,650,000,000
Fees relating to establishment of Credit Agreement	150,000,000
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	$ 1,390,000,000
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					$ 319,800,000			$ 319,800,000
Credit Agreement [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Senior secured long-term borrowing	$ 1,000,000,000
Credit Agreement [Member] \| Revolving Credit Facility [Member] \| Maximum [Member] \| Financial Letters of Credit [Member]
Debt Instrument [Line Items]
Avilable credit facility for issuance	200,000,000
Credit Agreement [Member] \| Revolving Credit Facility and Letter of Credit [Member]
Debt Instrument [Line Items]
Fees relating to establishment of Credit Agreement	57,000,000
Credit Agreement [Member] \| Term Facility [Member]
Debt Instrument [Line Items]
Senior secured long-term borrowing	2,260,000,000
Weighted average interest rate					7.27%			7.27%
Debt instrument periodic payment								$ 5,650,000
Fees relating to establishment of Credit Agreement	93,000,000
Credit Agreement [Member] \| Term Facility [Member] \| Letter of Credit Facility [Member]
Debt Instrument [Line Items]
Debt instrument issued or deemed issued					$ 278,000,000			278,000,000
Available capacity under credit facility					32,000,000			$ 32,000,000
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
Credit Agreement [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Fees relating to establishment of Credit Agreement		$ 59,000,000
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%
North Ocean Construction Financing [Member]
Debt Instrument [Line Items]
Term facility, borrowings outstanding Amount					20,000,000			$ 20,000,000		$ 25,000,000
North Ocean Construction Financing [Member] \| Secured Debt [Member] \| North Ocean 105 [Member]
Debt Instrument [Line Items]
Term facility, borrowings outstanding Amount					20,000,000			$ 20,000,000
Percentage of interest acquired in subsidiary			75.00%
Debt instrument frequency of installments								semiannual
Number of semiannual installments of principal repayment \| Installment			17
Principal repayment			$ 4,000,000
Debt instrument date of first installment payment			Oct. 01, 2012
Principal repayment, description								The financing agreement requires principal repayment in 17 consecutive semiannual installments of approximately $4 million, which commenced on October 1, 2012.
Ownership percentage in Oceanteam ASA's							25.00%
Purchase of vessel, cash consideration							$ 11,000,000
Note payable assumed							$ 5,000,000
Future maturities remainder of 2018					4,000,000			$ 4,000,000
Future maturities 2019					8,000,000			8,000,000
Future maturities 2020					$ 8,000,000			$ 8,000,000
8.000% Second-lien Senior Notes [Member]
Debt Instrument [Line Items]
Term facility, borrowings outstanding Amount										$ 500,000,000
Aggregate principal amount redeemed						$ 500,000,000
Debt instrument, interest rate						8.00%
Make-whole fees						$ 10,000,000
Write-off of deferred debt issuance costs						$ 4,000,000