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Litigation (Details) (USD $) | Mar. 31, 2014 | Dec. 31, 2013 | Mar. 31, 2013 | Aug. 31, 2011 Litigation related to construction materials [Member] | Oct. 31, 2010 Natural gas gathering operations [Member] | Jan. 13, 2012 Guarantee obligation under construction contract [Member] | Dec. 31, 2009 Guarantee obligation under construction contract [Member]
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Loss Contingencies [Line Items] |  |  |  |  |  |  |
Potential liabilities related to litigation and environmental matters | $ 31,400,000 | $ 29,500,000 | $ 33,300,000 |  |  |  |
Amount of compensatory damages in LPP's notice of demand |  |  |  |  |  |  | 149,700,000
Arbitration award |  |  |  |  | 26,600,000 | 22,000,000 |
Loss contingency, estimate of possible loss |  |  |  | 3,700,000 |  |  |
Additional amount per day of potential penalties |  |  |  | $ 5,000 |  |  |

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- Definition The amount accrued for potential liabilities related to litigation and enviromental matters as of the balance sheet date. + References No definition available. + Details
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- Definition Reflects the estimated amount of loss from the specified contingency as of the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 9 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14557-108349 + Details
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