Derivatives Derivatives (Schedule of Non-designated Hedges Outstanding) (Details)	12 Months Ended
	Dec. 31, 2016 $ / Unit MMBTU bbl
Natural gas | Swap | If Nymex | Jan'17 - Mar'17
Derivative Instruments, Gain (Loss) [Line Items]
Swap Price	3.044
Hedged Volume (MMBtu/day) | MMBTU	70,000
Natural gas | Swap | If Nymex | Apr'17 - Dec'17
Derivative Instruments, Gain (Loss) [Line Items]
Swap Price	2.960
Hedged Volume (MMBtu/day) | MMBTU	60,000
Natural gas | Swap | If Nymex | Jan'18 - Dec'18
Derivative Instruments, Gain (Loss) [Line Items]
Swap Price	3.025
Hedged Volume (MMBtu/day) | MMBTU	10,000
Natural gas | Basis Swap | If Nymex | Jan'17 - Dec'17
Derivative Instruments, Gain (Loss) [Line Items]
Swap Price	(0.215)	[1]
Hedged Volume (MMBtu/day) | MMBTU	20,000
Natural gas | Basis Swap | If Nymex | Jan'18 - Dec'18
Derivative Instruments, Gain (Loss) [Line Items]
Swap Price	(0.208)	[1]
Hedged Volume (MMBtu/day) | MMBTU	10,000
Natural gas | Collar | If Nymex | Jan'17 - Oct'17
Derivative Instruments, Gain (Loss) [Line Items]
Ceiling Price	3.10
Floor Price	2.88
Hedged Volume (MMBtu/day) | MMBTU	20,000
Natural gas | Three-way collar | If Nymex | Jan'17 - Dec'17
Derivative Instruments, Gain (Loss) [Line Items]
Ceiling Price	3.32
Subfloor Price	2.00
Floor Price	2.50
Hedged Volume (MMBtu/day) | MMBTU	15,000
Natural gas | Three-way collar | If Nymex | Jan'18 - Mar'18
Derivative Instruments, Gain (Loss) [Line Items]
Ceiling Price	4.43
Subfloor Price	2.50
Floor Price	3.25
Hedged Volume (MMBtu/day) | MMBTU	10,000
Crude Oil | Three-way collar | Wti Nymex | Jan'17 - Dec'17
Derivative Instruments, Gain (Loss) [Line Items]
Ceiling Price	60.98
Subfloor Price	39.58
Floor Price	49.79
Hedged Volume (Bbl/day) | bbl	3,750

[1] After December 31, 2016, the basis swaps for February through October 2017 and April through October 2018 were liquidated for $0.6 million and $0.5 million, respectively.