Decommissioning and Other Asset Retirement Obligations (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Decommissioning and Other Asset Retirement Obligations Detail [Table]
Beginning balance for the period, as reported	$ 94,921,000	$ 139,835,000
Activity in the period:
Accretion of liability	673,000	1,536,000
Retirement obligations incurred	0	0
Revisions in estimated cash flows	74,946,000	40,986,000
Settlement of retirement obligations	(119,636,000)	(87,436,000)
Ending balance at December 31	50,904,000	94,921,000	139,835,000
Change in estimated cash flows to decommission oil and gas properties	75,000,000	41.0
Direct charges to operating expense for increased estimated cash flows	75,312,000	40,767,000	78,382,000
Aggregate amount of asset retirement obligations assumed by buyers of oil and gas properties	5,300,000
Estimated future hurricane repair expenses	7,700,000
Asset retirement obligations associated with non-operated properties	$ 7,600,000	$ 7,500,000