v2.4.0.8

Asset Retirement Obligations (Tables)

9 Months Ended

Sep. 30, 2013

Asset Retirement Obligations [Abstract]

Reconciliation Of Beginning And Ending Aggregate Carrying Amount Of Asset Retirement Obligation

		September 30,			December 31,
(Thousands of dollars)		2013			2012
Balance at beginning of period		$	15,401			13,190
Accretion expense			821			980
Liabilities incurred			491			1,231
Balance at end of period		$	16,713			15,401

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- Definition

Tabular disclosure of the changes in carrying amount of a liability for asset retirement obligations, for changes such as new obligations, changes in estimates of existing obligations, spending on existing obligations, property dispositions, and foreign currency translation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 30

-Section 50

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13201-110859

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