Asset Retirement Obligations (Tables)

12 Months Ended

Dec. 31, 2019

Asset Retirement Obligation [Abstract]

Reconciliation of the company's asset retirement obligation

A reconciliation of the Company's liability, which is included in other accrued liabilities and deferred credits and other liabilities - other on the Consolidated Balance Sheets, for the years ended December 31 was as follows:

	2019			2018
	(In thousands)
Balance at beginning of year	$	375,553		$	341,969
Liabilities incurred	25,869			13,424
Liabilities acquired	486			1,002
Liabilities settled	(7,097		)	(3,699		)
Accretion expense*	19,789			18,242
Revisions in estimates	2,975			4,615
Balance at end of year	$	417,575		$	375,553

* Includes $18.3 million and $16.8 million in 2019 and 2018, respectively, related to regulatory assets.