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Asset Retirement Obligations (Tables)

12 Months Ended

Dec. 31, 2011

Asset Retirement Obligations [Abstract]

Activity Associated With Asset Retirement Obligations

		Years Ended December 31
		2011				2010				2009
Asset retirement obligations, beginning of year		$	2,975			$	3,031			$	3,009
Liabilities incurred			100				0				2,000
Accretion expense			165				139				168
Liabilities settled			0				0				(1,539	)
Changes in expected cash flows and timing			57				(195	)			(607	)
Asset retirement obligations, end of year		$	3,297			$	2,975			$	3,031

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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

-Topic 410

-SubTopic 30

-Publisher FASB

-Number

-Article

-Subparagraph

-Name Accounting Standards Codification

-Paragraph 5

-Section 50

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

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