Asset Retirement Obligations and Accrued Environmental Costs (Tables)

12 Months Ended

Dec. 31, 2014

Asset Retirement Obligations and Accrued Environmental Costs [Abstract]

Asset retirement obligations and accrued environmental costs

Note 9—Asset Retirement Obligations and Accrued Environmental Costs
Asset retirement obligations and accrued environmental costs at December 31 were:
	Millions of Dollars
	2014		2013
Asset retirement obligations	$	10,939	10,076
Accrued environmental costs		344	348
Total asset retirement obligations and accrued environmental costs		11,283	10,424
Asset retirement obligations and accrued environmental costs due within one year*		(636)	(541)
Long-term asset retirement obligations and accrued environmental costs	$	10,647	9,883
*Classified as a current liability on the balance sheet under "Other accruals" and includes $14 million of liabilities associated with assets held
for sale at December 31, 2013.

Changes in overall asset retirement obligation changed

During 2014 and 2013, our overall asset retirement obligation changed as follows:
	Millions of Dollars
	2014		2013
Balance at January 1	$	10,076	9,164
Accretion of discount		479	434
New obligations		368	410
Changes in estimates of existing obligations		1,175	707
Spending on existing obligations		(365)	(298)
Property dispositions		(20)	(163)
Foreign currency translation		(774)	(178)
Balance at December 31	$	10,939	10,076