Discontinued Operations and Disposal Groups (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended			9 Months Ended
	Sep. 30, 2014		Sep. 30, 2013	Sep. 30, 2014		Sep. 30, 2013	Dec. 31, 2013
Balance Sheet - Discontinued Operations
Assets held for sale - current	$ 5,375			$ 5,375			$ 7,661
Assets held for sale - non-current	176,694			176,694			178,484
Liabilities held for sale - current	3,070			3,070			12,069
Asset retirement obligations	(273)	[1]		(273)	[1]
Liabilities held for sale - non-current	61,543			61,543			55,915
Statement of Operations - Discontinued Operations
Impairment of Natural Gas and Crude Oil Properties	274		236	433		642
Income (loss) from discontinued operations, net of tax	(80)		(2,093)	392		409
Supplemental Cash Flow Information
Capital expenditures				(451,081)		(256,096)
Change in accounts payable related to purchases of properties and equipment				19,320		24,308
Assets Held-for-sale
Balance Sheet - Discontinued Operations
Cash and Cash Equivalents	496			496			601
Other current assets	4,879			4,879			7,060
Assets held for sale - current	5,375			5,375			7,661
Properties and equipment, net	169,672			169,672			171,592
Other assets	7,022			7,022			6,892
Assets held for sale - non-current	176,694			176,694			178,484
Liabilities held for sale - current	3,070			3,070			12,069
Long-term debt	59,750			59,750			52,000
Asset retirement obligations	273			273			2,234
Other liabilities	1,520			1,520			1,681
Liabilities held for sale - non-current	61,543			61,543			55,915
Net assets	117,456			117,456			118,161
PDCM Divestiture
Supplemental Cash Flow Information
Capital expenditures				(17,253)		(29,793)
Change in accounts payable related to purchases of properties and equipment				(5,727)		4,834
Discontinued Operations
Statement of Operations - Discontinued Operations
Crude oil, natural gas and NGL sales	5,411		4,738	24,149		32,525
Sales from natural gas marketing	0		1,789	0		2,825
Commodity price risk management gain (loss), net	1,929		500	(1,085)		806
Well operations, pipeline income and other	0		36	48		918
Total revenues	7,340		7,063	23,112		37,074
Production Costs	1,020		2,039	7,120		13,375
Cost of natural gas marketing	0		1,679	0		2,673
Impairment of Natural Gas and Crude Oil Properties	273		236	433		642
Depreciation, depletion and amortization	1,272		3,913	9,128		11,001
Other	1,061		1,299	3,445		6,092
Loss on sale of properties and equipment	(1)		642	(193)		1,702
Total costs, expenses and other	3,625		9,808	19,933		35,485
Interest Expense	(709)		(552)	(2,222)		(1,072)
Interest income	62		0	194		0
Income from discontinued operations	3,068		(3,297)	1,151		517
Provision for income taxes	(3,148)		1,204	(759)		(108)
Income (loss) from discontinued operations, net of tax	$ (80)		$ (2,093)	$ 392		$ 409

[1] Represents asset retirement obligations related to our assets held for sale. See Note 12, Assets Held for Sale, Divestitures and Discontinued Operations, and Note 15, Subsequent Event, for additional information regarding the sale of our interest in PDCM.