Asset retirement obligations

12 Months Ended

Dec. 31, 2021

Asset Retirement Obligation [Abstract]

Asset Retirement Obligations

The Company records obligations related to retirement costs of natural gas distribution mains and lines, natural gas transmission lines, natural gas storage wells, decommissioning of certain electric generating facilities, reclamation of certain aggregate properties, special handling and disposal of hazardous materials at certain electric generating facilities, natural gas distribution facilities and buildings, and certain other obligations as asset retirement obligations.

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


	2021		2020
	(In thousands)
Balance at beginning of year	$	446,919	$	417,575
Liabilities incurred	12,454		11,560
Liabilities acquired	1,805		1,378
Liabilities settled	(15,155)		(5,369)
Accretion expense*	21,214		21,668
Revisions in estimates	1,449		107
Balance at end of year	$	468,686	$	446,919

*Includes $19.6 million and $20.1 million in 2021 and 2020, respectively, recorded to regulatory assets.

The Company believes that largely all expenses related to asset retirement obligations at the Company's regulated operations will be recovered in rates over time and, accordingly, defers such expenses as regulatory assets. For more information on the Company's regulatory assets and liabilities, see Note 6.