Summary Of Significant Accounting Policies (Narrative) (Details)	3 Months Ended		12 Months Ended
	Sep. 30, 2015 USD ($) rig	Mar. 31, 2015 USD ($) rig	Dec. 31, 2015 USD ($) contract systems Unit MMcf	Dec. 31, 2014 USD ($) rig systems	Dec. 31, 2013 USD ($) rig	Dec. 31, 2012 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Number of daywork contracts | contract			9
Number of contracts, daywork expiring in one year | contract			5
Number of contracts, daywork expiring in two years | contract			4
Book Overdrafts			$ 22,100,000	$ 27,800,000
Concentration of cash			$ 2,300,000	18,400,000
Percentage of expected cash flows on undiscounted basis exceeding the carrying values of long-lived assets			99.00%
Impairment of contract drilling equipment			$ 8,314,000	74,318,000	$ 0
Assets held for sale			615,000	0
Impairment of gas gathering systems			26,966,000	7,068,000	0
Interest Costs Capitalized			21,700,000	32,200,000	33,700,000
Goodwill impairment			0	0	0
Additions to goodwill			$ 0	0	0
Percentage fair value exceeds carrying value for goodwill			19.00%
Goodwill deductible for tax purposes			$ 2,200,000
Intangible asset impairment			0	0	0
Amortization on intangible assets			0	0	700,000
Accumulated amortization on intangible assets			0	0	18,000,000
Directly related overhead costs capitalized			19,200,000	23,700,000	21,500,000
Average rates used for depreciation, depletion, and amortization per Boe			12.30	14.82	13.32
Unproved properties not being amortized			$ 337,099,000	485,568,000	545,588,000
Future discounted net cash flows discounted			10.00%
Unproved properties included in amortization			$ 114,400,000	73,700,000
Impairment of oil and natural gas properties			1,599,348,000	76,683,000	0
Non-cash ceiling test write-down net of tax			1,000,000,000	47,700,000
Revenues from transactions with operating segments of same entity			22,100,000	89,500,000	64,300,000
Eliminated associated operating expense			18,300,000	62,400,000	46,900,000
Eliminated yielding			$ 3,800,000	27,100,000	17,400,000
Number of partnerships | Unit			15
Unrecognized tax benefits			$ 410,000	$ 410,000	0	$ 0
Minimum
Summary Of Significant Accounting Policies [Line Items]
Number of days for drilling of one well			10 days
Duration length of contracts			6 months
Insurance coverage			$ 0
Maximum
Summary Of Significant Accounting Policies [Line Items]
Number of days for drilling of one well			90 days
Duration length of contracts			3 years
Insurance coverage			$ 1,000,000
Under-Produced Properties
Summary Of Significant Accounting Policies [Line Items]
Natural gas balancing (MMcf) | MMcf			4,700
Over-Produced Properties
Summary Of Significant Accounting Policies [Line Items]
Natural gas balancing (MMcf) | MMcf			4,800
Natural Gas Balancing
Summary Of Significant Accounting Policies [Line Items]
Accounts receivable			$ 2,500,000
Liability recognized to under production			$ 5,000,000
Drilling Equipment
Summary Of Significant Accounting Policies [Line Items]
Minimum depreciation percentage for idle drilling rigs			20.00%
Number of drilling rigs removed from service | rig				31
Drilling Equipment | Minimum
Summary Of Significant Accounting Policies [Line Items]
Useful life, years			15 years
Gas Gathering and Processing Equipment
Summary Of Significant Accounting Policies [Line Items]
Number of gas gathering systems impaired | systems			3	3
Property, Plant and Equipment, Other Types | Minimum
Summary Of Significant Accounting Policies [Line Items]
Useful life, years			3 years
Property, Plant and Equipment, Other Types | Maximum
Summary Of Significant Accounting Policies [Line Items]
Useful life, years			15 years
Drilling
Summary Of Significant Accounting Policies [Line Items]
Impairment of long-lived assets held-for-use			$ 0	$ 0	$ 0
Drilling Equipment
Summary Of Significant Accounting Policies [Line Items]
Number of rigs sold | rig	30	1		4	5
Net book value of drilling rigs sold	11.0	0.3		16.3
Gain (loss) on sale of drilling rigs	$ (7,300,000)	$ 7,900		$ 9,600,000	$ 16,500,000