Property, Plant and Equipment

12 Months Ended

Dec. 31, 2019

Property, Plant and Equipment [Abstract]

Note 4. Property, Plant and Equipment

The historical costs of our property, plant and equipment and related accumulated depreciation balances were as follows at the dates indicated:

	Estimated Useful Life			December 31,
	in Years			2019		2018
Plants, pipelines and facilities (1)		3-45	(5)	$	47,201.2	$	42,371.0
Underground and other storage facilities (2)		5-40	(6)		3,965.5		3,624.2
Transportation equipment (3)		3-10			198.9		187.1
Marine vessels (4)		15-30			905.9		828.6
Land					372.3		359.5
Construction in progress					2,641.2		3,526.8
Total					55,285.0		50,897.2
Less accumulated depreciation					13,681.6		12,159.6
Property, plant and equipment, net				$	41,603.4	$	38,737.6

(1)	Plants, pipelines and facilities include processing plants; NGL, natural gas, crude oil and petrochemical and refined products pipelines; terminal loading and unloading facilities; buildings; office furniture and equipment; laboratory and shop equipment and related assets. We placed a number of major growth projects into service during 2019 including the Shin Oak NGL pipeline, Midland-to-ECHO 2 pipeline, an isobutane dehydrogenation facility, the Mentone and Bulldog natural gas processing plants, and LPG-related expansion projects at our Enterprise Hydrocarbons Terminal.
(2)	Underground and other storage facilities include underground product storage caverns; above ground storage tanks; water wells and related assets.
(3)	Transportation equipment includes tractor-trailer tank trucks and other vehicles and similar assets used in our operations.
(4)	Marine vessels include tow boats, barges and related equipment used in our marine transportation business.
(5)	In general, the estimated useful lives of major assets within this category are: processing plants, 20-35 years; pipelines and related equipment, 5-45 years; terminal facilities, 10-35 years; buildings, 20-40 years; office furniture and equipment, 3-20 years; and laboratory and shop equipment, 5-35 years.
(6)	In general, the estimated useful lives of assets within this category are: underground storage facilities, 5-35 years; storage tanks, 10-40 years; and water wells, 5-35 years.

The following table summarizes our depreciation expense and capitalized interest amounts for the years indicated:

	For the Year Ended December 31,
	2019		2018		2017
Depreciation expense (1)	$	1,562.6	$	1,436.2	$	1,296.1
Capitalized interest (2)		143.8		147.9		192.1

(1)	Depreciation expense is a component of “Costs and expenses” as presented on our Statements of Consolidated Operations.
(2)	Capitalized interest is a component of “Interest expense” as presented on our Statements of Consolidated Operations.

Asset Retirement Obligations

We record AROs in connection with legal requirements to perform specified retirement activities under contractual arrangements and/or governmental regulations. Our contractual AROs primarily result from right-of-way agreements associated with our pipeline operations and property leases associated with our plant sites. In addition, we record AROs in connection with governmental regulations associated with the abandonment or retirement of above-ground brine storage pits and certain marine vessels. We also record AROs in connection with regulatory requirements associated with the renovation or demolition of certain assets containing hazardous substances such as asbestos. We typically fund our AROs using cash flow from operations.

Property, plant and equipment at December 31, 2019 and 2018 includes $69.6 million and $72.5 million, respectively, of asset retirement costs capitalized as an increase in the associated long-lived asset.

The following table presents information regarding our AROs for the years indicated:

	For the Year Ended December 31,
	2019			2018			2017
ARO liability beginning balance	$	126.3		$	86.7		$	85.4
Liabilities incurred		5.0			24.4			4.7
Liabilities settled		(2.3	)		(2.5	)		(2.2	)
Revisions in estimated cash flows		(4.8	)		11.5			(6.7	)
Accretion expense		7.9			6.2			5.5
ARO liability ending balance	$	132.1		$	126.3		$	86.7

The following table presents our forecast of ARO-related accretion expense for the years indicated:

2020				2021				2022				2023				2024
$	8.2			$	8.6			$	9.1			$	9.6			$	10.3