Property, Plant, and Equipment (Tables)

12 Months Ended

Dec. 31, 2020

Property, Plant and Equipment [Abstract]

Property, Plant, and Equipment [Table Text Block]

The following table presents nonregulated and regulated Property, plant, and equipment – net as presented on the Consolidated Balance Sheet for the years ended:

	Estimated Useful Life  (1) (Years)	Depreciation Rates (1) (%)	December 31,
			2020		2019
			(Millions)
Nonregulated:
Natural gas gathering and processing facilities	5 - 40		$	17,813	$	17,593
Construction in progress	Not applicable		289		354
Other	2 - 45		2,658		2,519
Regulated:
Natural gas transmission facilities		1.25 - 7.13	18,688		18,076
Construction in progress	Not applicable	Not applicable	382		586
Other	5 - 45	0.00 - 33.33	2,659		2,382
Total property, plant, and equipment, at cost			42,489		41,510
Accumulated depreciation and amortization			(13,560)		(12,310)
Property, plant, and equipment — net			$	28,929	$	29,200

__________

(1)    Estimated useful life and depreciation rates are presented as of December 31, 2020. Depreciation rates and estimated useful lives for regulated assets are prescribed by the FERC.

Schedule of Change in Asset Retirement Obligation

The following table presents the significant changes to our ARO, of which $1.159 billion and $1.117 billion are included in Regulatory liabilities, deferred income, and other with the remaining current portion in Accrued liabilities at December 31, 2020 and 2019, respectively.

	December 31,
	2020		2019
	(Millions)
Balance at beginning of year	$	1,165	$	1,032
Liabilities incurred (1)	37		15
Liabilities settled	(19)		(8)
Accretion expense	65		59
Revisions (2)	(26)		67
Balance at end of year	$	1,222	$	1,165

___________

(1)As a result of the global resolution with Chesapeake in 2020, we recorded $31 million of ARO related to natural gas properties transferred to us. (See Note 1 – General, Description of Business, Basis of Presentation, and Summary of Significant Accounting Policies.)

(2)Several factors are considered in the annual review process, including inflation rates, current estimates for removal cost, market risk premiums, discount rates, and the estimated remaining useful life of the assets. The 2020 revisions reflect changes in removal cost estimates, increases in the estimated remaining useful life of certain assets, decreases in inflation rates, and decreases in the discount rates used in the annual review process. The 2019 revisions reflect changes in removal cost estimates, decreases in the estimated remaining useful life of certain assets, increases in inflation rates, and decreases in the discount rates used in the annual review process.