Acquisitions and Divestitures (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Discontinued Operations and Disposal Groups [Abstract]
Net Gain (Loss) on Asset Dispositions	$ (16,758)	$ 9,147
Book Value of Assets Held for Sale	88,000
Asset Retirement Obligations	13,000
Proceeds from Sale of Oil and Gas Property and Equipment	$ 46,812	$ 6,667

Amount of asset retirement obligations settled through noncash transactions. An asset retirement obligation is a legal obligation associated with the disposal or retirement from service of a tangible long-lived asset.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4332-108586

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4313-108586

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration