Derivative And Financial Instruments (Hedges In Place) (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2016 USD ($) $ / bbl bbl
Derivative [Line Items]
Average Price | $ / bbl	65.65
Derivative, cash settlement receipts | $	$ 3,197
West Texas Intermediate 2016 Swap Quarter 4
Derivative [Line Items]
Volume (in Bbls)	49,802
Average Price | $ / bbl	48.25
West Texas Intermediate 2016
Derivative [Line Items]
Volume (in Bbls)	49,802
Average Price | $ / bbl	48.25
West Texas Intermediate 2017 Swap Quarter 1
Derivative [Line Items]
Volume (in Bbls)	57,953
Average Price | $ / bbl	68.06
West Texas Intermediate 2017 Swap Quarter 2
Derivative [Line Items]
Volume (in Bbls)	54,554
Average Price | $ / bbl	68.06
West Texas Intermediate 2017 Swap Quarter 3
Derivative [Line Items]
Volume (in Bbls)	51,570
Average Price | $ / bbl	68.06
West Texas Intermediate 2017 Swap Quarter 4
Derivative [Line Items]
Volume (in Bbls)	48,926
Average Price | $ / bbl	68.06
West Texas Intermediate 2017
Derivative [Line Items]
Volume (in Bbls)	213,003
Average Price | $ / bbl	68.06
West Texas Intermediate 2018 Swap Quarter 1
Derivative [Line Items]
Volume (in Bbls)	56,798
Average Price | $ / bbl	65.40
West Texas Intermediate 2018 Swap Quarter 2
Derivative [Line Items]
Volume (in Bbls)	54,197
Average Price | $ / bbl	65.40
West Texas Intermediate 2018 Swap Quarter 3
Derivative [Line Items]
Volume (in Bbls)	51,851
Average Price | $ / bbl	65.40
West Texas Intermediate 2018 Swap Quarter 4
Derivative [Line Items]
Volume (in Bbls)	49,709
Average Price | $ / bbl	65.40
West Texas Intermediate 2018
Derivative [Line Items]
Volume (in Bbls)	212,555
Average Price | $ / bbl	65.40
West Texas Intermediate 2019 Swap Quarter 1
Derivative [Line Items]
Volume (in Bbls)	52,760
Average Price | $ / bbl	65.65
West Texas Intermediate 2019 Swap Quarter 2
Derivative [Line Items]
Volume (in Bbls)	50,784
Average Price | $ / bbl	65.65
West Texas Intermediate 2019 Swap Quarter 3
Derivative [Line Items]
Volume (in Bbls)	48,960
West Texas Intermediate 2019 Swap Quarter 4
Derivative [Line Items]
Volume (in Bbls)	47,264
Average Price | $ / bbl	65.65
West Texas Intermediate 2019
Derivative [Line Items]
Volume (in Bbls)	199,768
Average Price | $ / bbl	65.65
West Texas Intermediate
Derivative [Line Items]
Volume (in Bbls)	675,128
NYMEX 2016 Swap Quarter 4
Derivative [Line Items]
Volume (in Bbls)	505,199
Average Price | $ / bbl	3.77
NYMEX 2016
Derivative [Line Items]
Volume (in Bbls)	505,199
Average Price | $ / bbl	3.77
NYMEX 2017 Swap Quarter 1
Derivative [Line Items]
Volume (in Bbls)	271,507
Average Price | $ / bbl	5.72
NYMEX 2017 Swap Quarter 2
Derivative [Line Items]
Volume (in Bbls)	255,669
Average Price | $ / bbl	5.72
NYMEX 2017 Swap Quarter 3
Derivative [Line Items]
Volume (in Bbls)	241,748
Average Price | $ / bbl	5.72
NYMEX 2017 Swap Quarter 4
Derivative [Line Items]
Volume (in Bbls)	229,122
Average Price | $ / bbl	5.72
NYMEX 2017
Derivative [Line Items]
Volume (in Bbls)	998,046
Average Price | $ / bbl	5.72
NYMEX 2018 Swap Quarter 1
Derivative [Line Items]
Volume (in Bbls)	79,042
Average Price | $ / bbl	3.58
NYMEX 2018 Swap Quarter 2
Derivative [Line Items]
Volume (in Bbls)	75,404
Average Price | $ / bbl	3.58
NYMEX 2018 Swap Quarter 3
Derivative [Line Items]
Volume (in Bbls)	72,115
Average Price | $ / bbl	3.58
NYMEX 2018 Swap Quarter 4
Derivative [Line Items]
Volume (in Bbls)	69,122
Average Price | $ / bbl	3.58
NYMEX 2018
Derivative [Line Items]
Volume (in Bbls)	295,683
Average Price | $ / bbl	3.58
NYMEX 2019 Swap Quarter 1
Derivative [Line Items]
Volume (in Bbls)	73,432
Average Price | $ / bbl	3.62
NYMEX 2019 Swap Quarter 2
Derivative [Line Items]
Volume (in Bbls)	70,648
Average Price | $ / bbl	3.62
NYMEX 2019 Swap Quarter 3
Derivative [Line Items]
Volume (in Bbls)	68,088
Average Price | $ / bbl	3.62
NYMEX 2019 Swap Quarter 4
Derivative [Line Items]
Volume (in Bbls)	65,720
Average Price | $ / bbl	3.62
NYMEX 2019
Derivative [Line Items]
Volume (in Bbls)	277,888
Average Price | $ / bbl	3.62
NYMEX
Derivative [Line Items]
Volume (in Bbls)	2,076,816