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Asset Retirement Obligation (Tables) | 12 Months Ended
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Dec. 31, 2013
Asset Retirement Obligation |
Asset Retirement Obligation |
(In thousands) |  | Year Ended December 31, 2013 |
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Balance at beginning of period |  | $ | 67,016 |
Liabilities incurred |  |  | 5,295 |
Liabilities settled |  |  | (762 | )
Liabilities divested |  |  | (6,400 | )
Accretion expense |  |  | 3,691 |
Change in estimate |  |  | 7,013 |
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Balance at end of period |  | $ | 75,853 |
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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 + Details
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