Asset Retirement Obligations

12 Months Ended

Dec. 31, 2020

Asset Retirement Obligation Disclosure [Abstract]

Asset Retirement Obligations

16. Asset Retirement Obligations

The following table presents the changes in asset retirement obligations.

	Year Ended December 31,
	2020			2019
Asset retirement obligations as of beginning of period	$	398		$	484
Liabilities incurred		18			20
Liabilities settled and divested		(29	)		(66	)
Liabilities reclassified as held for sale		(42	)		—
Revision of estimated obligation		4			(61	)
Accretion expense on discounted obligation		20			21
Asset retirement obligations as of end of period		369			398
Less current portion		11			18
Asset retirement obligations, long-term	$	358		$	380

During 2019, Devon reduced its asset retirement obligations by $61 million, primarily due to changes in the future cost estimates and retirement dates for its oil and gas assets. During 2019, Devon also reduced its asset retirement obligations by $42 million as a result of Devon’s 2019 divestitures. For additional information, see Note 2.