Asset Retirement Obligations (Tables)

6 Months Ended

Jun. 30, 2023

Asset Retirement Obligation Disclosure [Abstract]

Schedule of Reconciliation of Beginning and Ending Aggregate Carrying Amount of Asset Retirement Obligations

A reconciliation of the beginning and ending aggregate carrying amount of the ARO for the six-month periods ended June 30, 2023 and 2022 is shown in the following table.

(Thousands of dollars)	June 30, 2023		June 30, 2022
Balance at beginning of year	$	911,653	971,893
Accretion	22,521		23,439
Liabilities incurred	4,805		9,007
Revisions of previous estimates	(822)		—
Liabilities settled	(64,978)		(26,144)
Changes due to translation of foreign currencies	2,920		(3,650)
Balance at end of year	876,099		974,545
Current portion of liability at June 30 ¹	(32,771)		(110,653)
Noncurrent portion of liability at June 30	$	843,328	863,892

1 Included in “Other accrued liabilities” on the Consolidated Balance Sheets.