Decommissioning and Other Asset Retirement Obligations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Decommissioning and Other Asset Retirement Obligations Detail [Table]
Beginning balance for the period, as reported	$ 57,449	$ 62,741
Activity in the period:
Accretion of liability	2,249	2,000
Retirement obligations incurred	0	0	$ 39,187
Revisions in estimated cash flows		3,341
Settlement of retirement obligations	(4,040)	(10,633)
Ending balance at December 31	55,478	57,449	62,741
Change in estimated cash flows to decommission oil and gas properties	(180)
Direct charges to operating expense for increased estimated cash flows	2,629	2,661	$ 72,724
Estimated future hurricane repair expenses	7,900
Asset retirement obligations associated with non-operated properties	$ 9,400	$ 9,100