Derivative And Financial Instruments (Hedges In Place) (Details)	12 Months Ended
	Dec. 31, 2015 MMBTU $ / MMBTU $ / bbl bbl
West Texas Intermediate 2016 Swap Quarter 1 [Member]
Derivative [Line Items]
Volume (in Bbls) | bbl	121,005
Average Price | $ / bbl	73.53
West Texas Intermediate 2016 Swap Quarter 2 [Member]
Derivative [Line Items]
Volume (in Bbls) | bbl	113,226
Average Price | $ / bbl	73.77
West Texas Intermediate 2016 Swap Quarter 3 [Member]
Derivative [Line Items]
Volume (in Bbls) | bbl	106,483
Average Price | $ / bbl	73.95
West Texas Intermediate 2016 Swap Quarter 4 [Member]
Derivative [Line Items]
Volume (in Bbls) | bbl	100,525
Average Price | $ / bbl	74.10
West Texas Intermediate 2016 [Member]
Derivative [Line Items]
Volume (in Bbls) | bbl	441,239
Average Price | $ / bbl	73.82
West Texas Intermediate 2017 Swap Quarter 1 [Member]
Derivative [Line Items]
Volume (in Bbls) | bbl	57,953
Average Price | $ / bbl	64.80
West Texas Intermediate 2017 Swap Quarter 2 [Member]
Derivative [Line Items]
Volume (in Bbls) | bbl	54,554
Average Price | $ / bbl	64.80
West Texas Intermediate 2017 Swap Quarter 3 [Member]
Derivative [Line Items]
Volume (in Bbls) | bbl	51,570
Average Price | $ / bbl	64.80
West Texas Intermediate 2017 Swap Quarter 4 [Member]
Derivative [Line Items]
Volume (in Bbls) | bbl	48,926
Average Price | $ / bbl	64.80
West Texas Intermediate 2017 [Member]
Derivative [Line Items]
Volume (in Bbls) | bbl	213,003
Average Price | $ / bbl	64.80
West Texas Intermediate 2018 Swap Quarter 1 [Member]
Derivative [Line Items]
Volume (in Bbls) | bbl	56,798
Average Price | $ / bbl	65.40
West Texas Intermediate 2018 Swap Quarter 2 [Member]
Derivative [Line Items]
Volume (in Bbls) | bbl	54,197
Average Price | $ / bbl	65.40
West Texas Intermediate 2018 Swap Quarter 3 [Member]
Derivative [Line Items]
Volume (in Bbls) | bbl	51,851
Average Price | $ / bbl	65.40
West Texas Intermediate 2018 Swap Quarter 4 [Member]
Derivative [Line Items]
Volume (in Bbls) | bbl	49,709
Average Price | $ / bbl	65.40
West Texas Intermediate 2018 [Member]
Derivative [Line Items]
Volume (in Bbls) | bbl	212,555
Average Price | $ / bbl	65.40
West Texas Intermediate 2019 Swap Quarter 1 [Member]
Derivative [Line Items]
Volume (in Bbls) | bbl	52,760
Average Price | $ / bbl	65.65
West Texas Intermediate 2019 Swap Quarter 2 [Member]
Derivative [Line Items]
Volume (in Bbls) | bbl	50,784
Average Price | $ / bbl	65.65
West Texas Intermediate 2019 Swap Quarter 3 [Member]
Derivative [Line Items]
Volume (in Bbls) | bbl	48,960
Average Price | $ / bbl	65.65
West Texas Intermediate 2019 Swap Quarter 4 [Member]
Derivative [Line Items]
Volume (in Bbls) | bbl	47,264
Average Price | $ / bbl	65.65
West Texas Intermediate 2019 [Member]
Derivative [Line Items]
Volume (in Bbls) | bbl	199,768
Average Price | $ / bbl	65.65
West Texas Intermediate [Member]
Derivative [Line Items]
Volume (in Bbls) | bbl	1,066,565
NYMEX 2016 Swap Quarter 1 [Member]
Derivative [Line Items]
Volume (in MMBtu) | MMBTU	1,098,689
Average Price | $ / MMBTU	4.13
NYMEX 2016 Swap Quarter 2 [Member]
Derivative [Line Items]
Volume (in MMBtu) | MMBTU	1,048,146
Average Price | $ / MMBTU	4.14
NYMEX 2016 Swap Quarter 3 [Member]
Derivative [Line Items]
Volume (in MMBtu) | MMBTU	998,394
Average Price | $ / MMBTU	4.14
NYMEX 2016 Swap Quarter 4 [Member]
Derivative [Line Items]
Volume (in MMBtu) | MMBTU	963,327
Average Price | $ / MMBTU	4.14
NYMEX 2016 [Member]
Derivative [Line Items]
Volume (in MMBtu) | MMBTU	4,108,556
Average Price | $ / MMBTU	4.14
NYMEX 2017 Swap Quarter 1 [Member]
Derivative [Line Items]
Volume (in MMBtu) | MMBTU	80,563
Average Price | $ / MMBTU	3.52
NYMEX 2017 Swap Quarter 2 [Member]
Derivative [Line Items]
Volume (in MMBtu) | MMBTU	75,829
Average Price | $ / MMBTU	3.52
NYMEX 2017 Swap Quarter 3 [Member]
Derivative [Line Items]
Volume (in MMBtu) | MMBTU	71,672
Average Price | $ / MMBTU	3.52
NYMEX 2017 Swap Quarter 4 [Member]
Derivative [Line Items]
Volume (in MMBtu) | MMBTU	67,984
Average Price | $ / MMBTU	3.52
NYMEX 2017 [Member]
Derivative [Line Items]
Volume (in MMBtu) | MMBTU	296,048
Average Price | $ / MMBTU	3.52
NYMEX 2018 Swap Quarter 1 [Member]
Derivative [Line Items]
Volume (in MMBtu) | MMBTU	79,042
Average Price | $ / MMBTU	3.58
NYMEX 2018 Swap Quarter 2 [Member]
Derivative [Line Items]
Volume (in MMBtu) | MMBTU	75,404
Average Price | $ / MMBTU	3.58
NYMEX 2018 Swap Quarter 3 [Member]
Derivative [Line Items]
Volume (in MMBtu) | MMBTU	72,115
Average Price | $ / MMBTU	3.58
NYMEX 2018 Swap Quarter 4 [Member]
Derivative [Line Items]
Volume (in MMBtu) | MMBTU	69,122
Average Price | $ / MMBTU	3.58
NYMEX 2018 [Member]
Derivative [Line Items]
Volume (in MMBtu) | MMBTU	295,683
Average Price | $ / MMBTU	3.58
NYMEX 2019 Swap Quarter 1 [Member]
Derivative [Line Items]
Volume (in MMBtu) | MMBTU	73,432
Average Price | $ / MMBTU	3.62
NYMEX 2019 Swap Quarter 2 [Member]
Derivative [Line Items]
Volume (in MMBtu) | MMBTU	70,648
Average Price | $ / MMBTU	3.62
NYMEX 2019 Swap Quarter 3 [Member]
Derivative [Line Items]
Volume (in MMBtu) | MMBTU	68,088
Average Price | $ / MMBTU	3.62
NYMEX 2019 Swap Quarter 4 [Member]
Derivative [Line Items]
Volume (in MMBtu) | MMBTU	65,720
Average Price | $ / MMBTU	3.62
NYMEX 2019 [Member]
Derivative [Line Items]
Volume (in MMBtu) | MMBTU	277,888
Average Price | $ / MMBTU	3.62
NYMEX [Member]
Derivative [Line Items]
Volume (in MMBtu) | MMBTU	4,978,175