Property, Plant and Equipment (Notes)

12 Months Ended

Dec. 31, 2020

Property, Plant and Equipment [Abstract]

6. Property, Plant and Equipment, net

Classes and Depreciation

As of December 31, 2020 and 2019, our property, plant and equipment, net consisted of the following:


	December 31,
	2020		2019
	(In millions)
Pipelines (Natural gas, liquids, crude oil and CO2)	$	20,339	$	19,856
Equipment (Natural gas, liquids, crude oil, CO2, and terminals)	26,142		25,791
Other(a)	5,188		5,360
Accumulated depreciation, depletion and amortization	(17,818)		(16,950)
	33,851		34,057
Land and land rights-of-way	1,403		1,356
Construction work in process	582		1,006
Property, plant and equipment, net	$	35,836	$	36,419

(a) Includes general plant, general structures and buildings, computer and communication equipment, intangibles, vessels, transmix products, linefill and miscellaneous property, plant and equipment.

As of December 31, 2020 and 2019, property, plant and equipment, net included $12,160 million and $12,229 million, respectively, of assets which were regulated by the FERC. Depreciation, depletion, and amortization expense charged against property, plant and equipment was $1,928 million, $2,176 million, and $2,057 million for the years ended December 31, 2020, 2019, and 2018, respectively.

Asset Retirement Obligations

As of December 31, 2020 and 2019, we recognized asset retirement obligations in the aggregate amount of $214 million and $218 million, respectively, of which $4 million were classified as current for both periods. The majority of our asset retirement obligations are associated with our CO2 business segment, where we are required to plug and abandon oil and gas wells that have been removed from service and to remove the surface wellhead equipment and compressors.