Property, Plant and Equipment - Additional Information (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2018 USD ($) Rig	Dec. 31, 2017 USD ($) Rig	Dec. 31, 2016 USD ($) Rig
Property, Plant and Equipment [Line Items]
Capitalized interest related to the construction and upgrade of qualifying assets	$ 27	$ 37	$ 51
Asset impairment loss, before tax and noncontrolling interests	44	106	697
Diamond Offshore [Member]
Property, Plant and Equipment [Line Items]
Asset impairment loss, before tax and noncontrolling interests	27	100	672
Asset impairment loss, net of tax and noncontrolling interests	$ 12	$ 32	$ 263
Diamond Offshore [Member] | Drilling Rigs [Member]
Property, Plant and Equipment [Line Items]
Number rigs evaluated for impairment | Rig	1	10	15
Number of rigs impaired | Rig	0	3	8
Number of drilling rigs | Rig	12
Number of rigs fair value using income approach | Rig		2
Number of rigs previously impaired | Rig			1
Boardwalk Pipeline [Member]
Property, Plant and Equipment [Line Items]
Proceed from sale of plant and equipment		$ 64
Gain (loss) on sale of plant and equipment		(47)
Gain (loss) on sale of plant and equipment,net of tax and noncontrolling interests		(15)
Consolidated Container [Member]
Property, Plant and Equipment [Line Items]
Balance of other property, plant and equipment		$ 366