Commitments and Contingencies Commitments and Contingencies (Details Textual) $ in Millions	Jun. 30, 2016 USD ($)
Office Lease Obligation [Member]
Debt Instrument [Line Items]
Operating Leases, Future Minimum Payments Due	$ 2.1
Gas transportation and processing obligations [Member]
Debt Instrument [Line Items]
Operating Leases, Future Minimum Payments Due	41.9
Operating Leases, Future Minimum Payments Due, Next Twelve Months	7.7
Operating Leases, Future Minimum Payments, Due in Two Years	9.3
Operating Leases, Future Minimum Payments, Due in Three Years	8.7
Operating Leases, Future Minimum Payments, Due in Four Years	8.3
Operating Leases, Future Minimum Payments, Due in Five Years	$ 7.9