Derivative Instruments--Outstanding Derivatives (Details) (USD $) In Thousands, unless otherwise specified												3 Months Ended
	Sep. 30, 2014 Swaps Derivatives Maturing in 2014 Oil Derivative bbl	Sep. 30, 2014 Swaps Derivatives Maturing in 2014 Natural Gas Derivative MMBTU	Sep. 30, 2014 Swaps Derivatives Maturing in 2015 Oil Derivative bbl	Sep. 30, 2014 Swaps Derivatives Maturing in 2015 Natural Gas Derivative MMBTU	Sep. 30, 2014 Swaps Derivatives Maturing in 2016 Natural Gas Derivative MMBTU	Sep. 30, 2014 Costless Collars Derivatives Maturing in 2014 Oil Derivative bbl	Sep. 30, 2014 Costless Collars Derivatives Maturing in 2016 Oil Derivative bbl	Sep. 30, 2014 Enhanced Swaps Derivatives Maturing in 2014 Oil Derivative bbl	Sep. 30, 2014 Enhanced Swaps Derivatives Maturing in 2015 Oil Derivative bbl	Sep. 30, 2014 Enhanced Swaps Derivatives Maturing in 2016 Oil Derivative bbl	Sep. 30, 2014 Put Spread Enhanced Swaps Derivatives Maturing in 2014 Oil Derivative bbl	Jun. 30, 2014 Purchased Puts Oil Derivative	Jun. 30, 2013 Purchased Puts Oil Derivative	Sep. 30, 2014 Purchased Puts Derivatives Maturing in 2014 Oil Derivative bbl		Jun. 30, 2013 Purchased Puts Derivatives Maturing in 2014 Oil Derivative bbl	Sep. 30, 2014 Purchased Puts Derivatives Maturing in 2015 Oil Derivative bbl		Sep. 30, 2014 Basis Protection Swaps Derivatives Maturing in 2014 Natural Gas Derivative MMBTU	Sep. 30, 2014 Basis Protection Swaps Derivatives Maturing in 2015 Natural Gas Derivative MMBTU
Derivative [Line Items]
Volume of derivative instruments held	187,000	5,090,000	600,000	22,170,000	7,800,000	600,000	240,000	210,000	6,058,000	3,720,000	745,000			210,000	[1]	840,000	5,548,000	[1]	5,200,000	2,400,000
Weighted average fixed price per unit, swaps	93.13	4.11	96.02	4.20	4.33			97.58	92.92	92.94	93.87								0.24	0.18
Weighted average fixed price per Bbl, sold puts						75.50	84.00	80.00	80.00	80.52	80.00
Weighted average fixed price per Bbl, purchased puts						93.25	92.00				60.00			60.00	[1]		60.00	[1]
Weighted average fixed price per Bbl, sold calls						101.94	101.01
Premium paid for put options on commodity derivative contracts												$ 1,220	$ 664

[1] Puts covering 840 Mbbls in 2014 were purchased during the second quarter of 2013 for $664. The 2015 puts were purchased during the second quarter of 2014 for $1,220.