Property, Plant and Equipment - Additional Information (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2016 USD ($) Well	Sep. 30, 2015 USD ($)	Sep. 30, 2016 USD ($) Well	Sep. 30, 2015 USD ($)	Dec. 31, 2015 USD ($) Well
Property, Plant and Equipment [Abstract]
Capitalized costs excluded from depletion	$ 1,210,684		$ 1,210,684		$ 618,794
Depletion expense on capitalized oil and gas properties	$ 63,900	$ 44,800	$ 166,400	$ 124,300
Number of exploratory wells in progress \| Well	0		0		0

The sum of the capitalized costs incurred, as of the balance sheet date, of unproved properties excluded from amortization including acquisition costs, exploration costs, development costs, and production costs.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-10.(c)(7)(ii))
-URI http://asc.fasb.org/extlink&oid=50486907&loc=d3e511914-122862

Name:	us-gaap_CapitalizedCostsOfUnprovedPropertiesExcludedFromAmortizationCumulative
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant