Derivative Instruments and Hedging Activities (Schedule of Outstanding Oil and Natural Gas Derivative Contracts) (Details) - Not Designated as Hedging Instrument [Member]	2 Months Ended	12 Months Ended
	Feb. 29, 2016 MMBTU $ / MMBTU $ / bbl MBbls	Dec. 31, 2015 $ / bbl MBbls
Collar Contracts Combined With Short Puts Three Months Ended March 31, 2016 [Member] | Crude Oil [Member]
Derivative [Line Items]
Total volume | MBbls		182
Collar Contracts Combined With Short Puts Three Months Ended March 31, 2016 [Member] | Crude Oil [Member] | Subsequent Event [Member]
Derivative [Line Items]
Total volume | MBbls	120
Collar Contracts Combined With Short Puts Three Months Ended March 31, 2016 [Member] | Crude Oil [Member] | Call Option [Member] | Short [Member]
Derivative [Line Items]
Strike price		65.00
Collar Contracts Combined With Short Puts Three Months Ended March 31, 2016 [Member] | Crude Oil [Member] | Call Option [Member] | Short [Member] | Subsequent Event [Member]
Derivative [Line Items]
Strike price	46.50
Collar Contracts Combined With Short Puts Three Months Ended March 31, 2016 [Member] | Crude Oil [Member] | Put Option [Member] | Long [Member]
Derivative [Line Items]
Strike price		55.00
Collar Contracts Combined With Short Puts Three Months Ended March 31, 2016 [Member] | Crude Oil [Member] | Put Option [Member] | Long [Member] | Subsequent Event [Member]
Derivative [Line Items]
Strike price	37.50
Collar Contracts Combined With Short Puts Three Months Ended March 31, 2016 [Member] | Crude Oil [Member] | Put Option [Member] | Short [Member]
Derivative [Line Items]
Strike price		40.33
Collar Contracts Combined With Short Puts Three Months Ended June 30, 2016 [Member] | Crude Oil [Member]
Derivative [Line Items]
Total volume | MBbls		182
Collar Contracts Combined With Short Puts Three Months Ended June 30, 2016 [Member] | Crude Oil [Member] | Subsequent Event [Member]
Derivative [Line Items]
Total volume | MBbls	182
Collar Contracts Combined With Short Puts Three Months Ended June 30, 2016 [Member] | Crude Oil [Member] | Call Option [Member] | Short [Member]
Derivative [Line Items]
Strike price		65.00
Collar Contracts Combined With Short Puts Three Months Ended June 30, 2016 [Member] | Crude Oil [Member] | Call Option [Member] | Short [Member] | Subsequent Event [Member]
Derivative [Line Items]
Strike price	46.50
Collar Contracts Combined With Short Puts Three Months Ended June 30, 2016 [Member] | Crude Oil [Member] | Put Option [Member] | Long [Member]
Derivative [Line Items]
Strike price		55.00
Collar Contracts Combined With Short Puts Three Months Ended June 30, 2016 [Member] | Crude Oil [Member] | Put Option [Member] | Long [Member] | Subsequent Event [Member]
Derivative [Line Items]
Strike price	37.50
Collar Contracts Combined With Short Puts Three Months Ended June 30, 2016 [Member] | Crude Oil [Member] | Put Option [Member] | Short [Member]
Derivative [Line Items]
Strike price		40.33
Collar Contracts Combined With Short Puts Three Months Ended September 30, 2016 [Member] | Crude Oil [Member]
Derivative [Line Items]
Total volume | MBbls		184
Collar Contracts Combined With Short Puts Three Months Ended September 30, 2016 [Member] | Crude Oil [Member] | Subsequent Event [Member]
Derivative [Line Items]
Total volume | MBbls	184
Collar Contracts Combined With Short Puts Three Months Ended September 30, 2016 [Member] | Crude Oil [Member] | Call Option [Member] | Short [Member]
Derivative [Line Items]
Strike price		65.00
Collar Contracts Combined With Short Puts Three Months Ended September 30, 2016 [Member] | Crude Oil [Member] | Call Option [Member] | Short [Member] | Subsequent Event [Member]
Derivative [Line Items]
Strike price	46.50
Collar Contracts Combined With Short Puts Three Months Ended September 30, 2016 [Member] | Crude Oil [Member] | Put Option [Member] | Long [Member]
Derivative [Line Items]
Strike price		55.00
Collar Contracts Combined With Short Puts Three Months Ended September 30, 2016 [Member] | Crude Oil [Member] | Put Option [Member] | Long [Member] | Subsequent Event [Member]
Derivative [Line Items]
Strike price	37.50
Collar Contracts Combined With Short Puts Three Months Ended September 30, 2016 [Member] | Crude Oil [Member] | Put Option [Member] | Short [Member]
Derivative [Line Items]
Strike price		40.33
Collar Contracts Combined With Short Puts Three Months Ended December 31, 2016 [Member] | Crude Oil [Member]
Derivative [Line Items]
Total volume | MBbls		184
Collar Contracts Combined With Short Puts Three Months Ended December 31, 2016 [Member] | Crude Oil [Member] | Subsequent Event [Member]
Derivative [Line Items]
Total volume | MBbls	184
Collar Contracts Combined With Short Puts Three Months Ended December 31, 2016 [Member] | Crude Oil [Member] | Call Option [Member] | Short [Member]
Derivative [Line Items]
Strike price		65.00
Collar Contracts Combined With Short Puts Three Months Ended December 31, 2016 [Member] | Crude Oil [Member] | Call Option [Member] | Short [Member] | Subsequent Event [Member]
Derivative [Line Items]
Strike price	46.50
Collar Contracts Combined With Short Puts Three Months Ended December 31, 2016 [Member] | Crude Oil [Member] | Put Option [Member] | Long [Member]
Derivative [Line Items]
Strike price		55.00
Collar Contracts Combined With Short Puts Three Months Ended December 31, 2016 [Member] | Crude Oil [Member] | Put Option [Member] | Long [Member] | Subsequent Event [Member]
Derivative [Line Items]
Strike price	37.50
Collar Contracts Combined With Short Puts Three Months Ended December 31, 2016 [Member] | Crude Oil [Member] | Put Option [Member] | Short [Member]
Derivative [Line Items]
Strike price		40.33
Swap Contracts Three Months Ended March 31, 2016 [Member] | Crude Oil [Member]
Derivative [Line Items]
Total volume | MBbls		182
Average swap price		58.23
Swap Contracts Three Months Ended March 31, 2016 [Member] | Natural Gas [Member] | Swap [Member] | Subsequent Event [Member]
Derivative [Line Items]
Total volume | MMBTU	360
Average swap price | $ / MMBTU	2.52
Swap Contracts Three Months Ended June 30, 2016 [Member] | Crude Oil [Member]
Derivative [Line Items]
Total volume | MBbls		182
Average swap price		58.23
Swap Contracts Three Months Ended June 30, 2016 [Member] | Natural Gas [Member] | Swap [Member] | Subsequent Event [Member]
Derivative [Line Items]
Total volume | MMBTU	546
Average swap price | $ / MMBTU	2.52
Swap Contracts Three Months Ended September 30, 2016 [Member] | Crude Oil [Member]
Derivative [Line Items]
Total volume | MBbls		184
Average swap price		58.23
Swap Contracts Three Months Ended September 30, 2016 [Member] | Natural Gas [Member] | Swap [Member] | Subsequent Event [Member]
Derivative [Line Items]
Total volume | MMBTU	552
Average swap price | $ / MMBTU	2.52
Swap Contracts Three Months Ended December 31, 2016 [Member] | Crude Oil [Member]
Derivative [Line Items]
Total volume | MBbls		184
Average swap price		58.23
Swap Contracts Three Months Ended December 31, 2016 [Member] | Natural Gas [Member] | Swap [Member] | Subsequent Event [Member]
Derivative [Line Items]
Total volume | MMBTU	552
Average swap price | $ / MMBTU	2.52
Swap Contracts Differentials Three Months Ended March 31, 2016 [Member] | Crude Oil [Member]
Derivative [Line Items]
Total volume | MBbls		364
Swap Contracts Differentials Three Months Ended March 31, 2016 [Member] | Crude Oil [Member] | Swap [Member]
Derivative [Line Items]
Average swap price		0.17
Swap Contracts Differentials Three Months Ended June 30, 2016 [Member] | Crude Oil [Member]
Derivative [Line Items]
Total volume | MBbls		364
Swap Contracts Differentials Three Months Ended June 30, 2016 [Member] | Crude Oil [Member] | Swap [Member]
Derivative [Line Items]
Average swap price		0.17
Swap Contracts Differentials Three Months Ended September 30, 2016 [Member] | Crude Oil [Member]
Derivative [Line Items]
Total volume | MBbls		368
Swap Contracts Differentials Three Months Ended September 30, 2016 [Member] | Crude Oil [Member] | Swap [Member]
Derivative [Line Items]
Average swap price		0.17
Swap Contracts Differentials Three Months Ended December 31, 2016 [Member] | Crude Oil [Member]
Derivative [Line Items]
Total volume | MBbls		368
Swap Contracts Differentials Three Months Ended December 31, 2016 [Member] | Crude Oil [Member] | Swap [Member]
Derivative [Line Items]
Average swap price		0.17
Short Call Contracts Three Months March 31, 2017 [Member] | Crude Oil [Member] | Call Option [Member] | Subsequent Event [Member]
Derivative [Line Items]
Total volume | MBbls	165
Strike price	50.00
Short Call Contracts Three Months June 30, 2017 [Member] | Crude Oil [Member] | Call Option [Member] | Subsequent Event [Member]
Derivative [Line Items]
Total volume | MBbls	167
Strike price	50.00
Short Call Contracts Three Months September 30, 2017 [Member] | Crude Oil [Member] | Call Option [Member] | Subsequent Event [Member]
Derivative [Line Items]
Total volume | MBbls	169
Strike price	50.00
Short Short Call Contracts Three Months December 31, 2017 [Member] | Crude Oil [Member] | Call Option [Member] | Subsequent Event [Member]
Derivative [Line Items]
Total volume | MBbls	169
Strike price	50.00