Revenue Recognition - Additional Information (Detail) - USD ($)		3 Months Ended		9 Months Ended
		Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Revenues recognized due to changes in transaction price	[1]	$ 2,121,000,000	$ 2,289,000,000	$ 6,469,000,000	$ 4,632,000,000
Revenue included from settlement of claims		119,000,000		119,000,000
Advance billings on contracts		179,000,000		1,500,000,000
Unapproved change orders and claims		406,000,000		406,000,000		$ 428,000,000
Unapproved change orders and claims in our RPO balance		94,000,000		94,000,000		130,000,000
Incentives amount included in transaction prices		214,000,000		214,000,000		0
Incentives amount included in our RPO balance		$ 43,000,000		$ 43,000,000
Estimated percentage of in progress as of combination date		0.00%		0.00%
Effect of changes in estimated project cost on operating results			79,000,000		200,000,000
Uncompleted Contracts [Member]
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Provisions for estimated losses		$ 131,000,000		$ 131,000,000		$ 266,000,000
Cameron Liquefied Natural Gas Project [Member]
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Provisions for estimated losses		70,000,000		70,000,000
Freeport LNG Train 3 Project [Member]
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Effect of changes in estimated project cost on operating results				95,000,000
NCSA [Member]
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Revenues recognized due to changes in transaction price		47,000,000		143,000,000
Effect of changes in estimated project cost on operating results		330,000,000	18,000,000	485,000,000	18,000,000
NCSA [Member] | Cameron Liquefied Natural Gas Project [Member]
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Provisions for estimated losses		$ 70,000,000		$ 70,000,000
Percentage of complete acquired on post combination basis		79.00%		79.00%
Percentage of complete acquired on pre combination basis		93.00%		93.00%
Effect of changes in estimated project cost on operating results		$ 170,000,000		$ 170,000,000
Revenue recognized achievement of progress milestones		90,000,000		200,000,000
NCSA [Member] | Freeport LNG Trains 1 and 2 Project [Member]
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Provisions for estimated losses		$ 8,000,000		$ 8,000,000
Percentage of complete acquired on post combination basis		96.00%		96.00%
Percentage of complete acquired on pre combination basis		99.00%		99.00%
Effect of changes in estimated project cost on operating results		$ 42,000,000		$ 96,000,000
Incentive revenues recognized				5,000,000
NCSA [Member] | Freeport LNG Train 3 Project [Member]
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Effect of changes in estimated project cost on operating results		9,000,000		4,000,000
NCSA [Member] | Asheville Power Plant Project [Member]
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Provisions for estimated losses		4,000,000		4,000,000
Effect of changes in estimated project cost on operating results		$ 60,000,000		$ 88,000,000
Percentage of completion		95.00%		95.00%
NCSA [Member] | Line 1 and Line 10 project for Pemex [Member]
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Provisions for estimated losses		$ 2,000,000		$ 2,000,000
Effect of changes in estimated project cost on operating results		$ 3,000,000		$ 31,000,000
Percentage of completion		95.00%		95.00%
NCSA [Member] | Calpine Power Project [Member]
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Percentage of complete acquired on post combination basis		98.00%		98.00%
Percentage of complete acquired on pre combination basis		100.00%		100.00%
Effect of changes in estimated project cost on operating results		$ 11,000,000		$ 22,000,000
APAC [Member]
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Revenues recognized due to changes in transaction price			$ 0		$ 81,000,000
Pemex [Member] | Abkatun-A2 Project [Member]
Revenue Recognition Multiple Deliverable Arrangements [Line Items]
Percentage of project acquired complete		99.00%		99.00%

[1] Intercompany amounts have been eliminated in consolidation.