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]
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