Property, Plant and Equipment (Tables)

6 Months Ended

Jun. 30, 2021

Property, Plant and Equipment [Abstract]

Property, Plant and Equipment and Accumulated Depreciation

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

	Estimated Useful Life in Years			June 30, 2021		December 31, 2020
Plants, pipelines and facilities (1)		3-45	(5)	$	50,419.7	$	49,972.8
Underground and other storage facilities (2)		5-40	(6)		4,240.9		4,207.5
Transportation equipment (3)		3-10			209.4		204.9
Marine vessels (4)		15-30			930.0		932.7
Land					383.0		371.9
Construction in progress					2,149.1		1,807.7
Subtotal					58,332.1		57,497.5
Less accumulated depreciation					16,191.5		15,584.7
Subtotal property, plant and equipment, net					42,140.6		41,912.8
Capitalized major maintenance costs for reaction-based    plants, net of accumulated amortization (7)					92.5		–
Property, plant and equipment, net				$	42,233.1	$	41,912.8

(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.
(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.
(7)	For reaction-based plants, we use the deferral method when accounting for major maintenance activities.  Under the deferral method, major maintenance costs are capitalized and amortized over the period until the next major overhaul project.   On a weighted-average basis, the expected amortization period for these costs is 2.9 years.

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

	For the Three Months Ended June 30,				For the Six Months Ended June 30,
	2021		2020		2021		2020
Depreciation expense (1)	$	424.0	$	418.7	$	847.7	$	830.9
Accretion expense (1)		2.1		8.4		3.8		10.2
Capitalized interest (2)		21.2		31.9		40.8		62.4

(1)

Depreciation and accretion expense is a component of “Third party and other costs” within “Costs and expenses” as presented on our Unaudited Condensed Statements of Consolidated Operations.

(2)

We capitalize interest costs incurred on funds used to construct property, plant and equipment while the asset is in its construction phase.  The capitalized interest is recorded as part of the asset to which it relates and is amortized over the asset’s estimated useful life as a component of depreciation expense.  When capitalized interest is recorded, it reduces interest expense from what it would be otherwise.

AROs

The following table presents information regarding our asset retirement obligations, or AROs, since December 31, 2020:

ARO liability balance, December 31, 2020	$	149.5
Liabilities incurred (1)		6.2
Revisions in estimated cash flows (2)		4.0
Liabilities settled (3)		(0.3	)
Accretion expense (4)		3.8
ARO liability balance, June 30, 2021	$	163.2

(1)	Represents the initial recognition of estimated ARO liabilities during period.
(2)	Represents subsequent adjustments to estimated ARO liabilities during period.
(3)	Represents cash payments to settle ARO liabilities during period.
(4)	Represents net change in ARO liability balance attributable to the passage of time and other adjustments, including true-up amounts associated with revised closure estimates.