Property, Plant and Equipment, Components of Property, Plant and Equipment (Details) - USD ($) $ in Millions		Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Abstract]
Construction in process		$ 281	$ 595
Property, plant and equipment		10,451	15,568
Pipeline Equipment [Member]
Property, Plant and Equipment [Abstract]
Property, plant and equipment		8,368	8,229
Accumulated depreciation		3,402	3,075
Hotel Properties [Member]
Property, Plant and Equipment [Abstract]
Property, plant and equipment		1,083	839
Accumulated depreciation		439	393
Offshore Drilling Equipment [Member]
Property, Plant and Equipment [Abstract]
Property, plant and equipment	[1]		5,119
Accumulated depreciation			2,885
Other [Member]
Property, Plant and Equipment [Abstract]
Property, plant and equipment		719	786
Accumulated depreciation		$ 688	$ 721

[1] Amounts presented for Diamond Offshore reflect the periods prior to deconsolidation. See Notes 2 and 20 for further discussion.