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Asset Retirement Obligations (Table)

12 Months Ended

Dec. 31, 2012

Asset Retirement Obligation [Abstract]

Asset retirement obligations

(Dollars in thousands)		2012			2011
Balance, beginning of period		$	143,402		$	128,709
	Additional liabilities accrued		5,578			2,105
	Revisions in estimated cash outflows (1)		22,588			5,888
	Disposition of assets		(2,674)			(1,323)
	Accretion expense (2)		10,713			8,023
Balance, end of period		$	179,607		$	143,402
(1)	In 2012, included $14.9 million as a result of changes in expected settlement dates related to the Divestiture Transaction.
(2)	In 2012, included $0.2 million of incremental accretion related to the Divestiture Transaction.

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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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