Property, Plant and Equipment - Additional Information (Detail) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2019 USD ($)	Dec. 31, 2019 USD ($) Acquisition	Dec. 31, 2018 USD ($) Acquisition	Dec. 31, 2017 USD ($) Rig
Property, Plant and Equipment [Line Items]
Capitalized interest related to the construction and upgrade of qualifying assets		$ 18	$ 27	$ 37
Asset impairment loss, before tax and noncontrolling interests		99	44	106
Impairment charges net of tax	$ 69
Impairment loss on plant property equipment		62	16
Impairment loss on other assets		37	6
Diamond Offshore [Member]
Property, Plant and Equipment [Line Items]
Asset impairment loss, before tax and noncontrolling interests			27	100
Asset impairment loss, net of tax and noncontrolling interests			12	$ 32
Diamond Offshore [Member] | Drilling Rigs [Member]
Property, Plant and Equipment [Line Items]
Number rigs evaluated for impairment | Rig				10
Number of rigs impaired | Rig				3
Number of rigs fair value using income approach | Rig				2
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
Loews Hotels And Co [Member]
Property, Plant and Equipment [Line Items]
Asset impairment loss, before tax and noncontrolling interests		99	22
Impairment charges net of tax		$ 77	$ 15
Number of hotels impaired | Acquisition		4	2