Long-Term Debt--Senior Secured Revolving Credit Facility (Details) (USD $)	1 Months Ended		3 Months Ended		9 Months Ended
	Jul. 31, 2014 Divestiture	May 31, 2014 Divestiture	Sep. 30, 2014 Divestiture	Aug. 13, 2014 Line of Credit	Sep. 30, 2014 Line of Credit	Jul. 18, 2014 Line of Credit	Nov. 05, 2014 Line of Credit Subsequent Event	Aug. 14, 2014 Minimum Line of Credit
Line of Credit Facility [Line Items]
Maturity date					Nov. 01, 2017
Proceeds from senior secured revolving credit facility					$ 185,000,000
Repayments on senior secured revolving credit facility					225,000,000
Debt, Weighted Average Interest Rate					1.90%
Number of divestitures	2	2	2
Borrowing base amount						$ 484,500,000	$ 650,000,000
Reduction in availability under the revolving credit facility, as a percentage of the borrowing base				10.00%
Ratio of credit availability to liability on overhedged production								2