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Restricted Certificates of Deposit	6 Months Ended
Restricted Certificates of Deposit	Jun. 30, 2016
Certificates Of Deposit [Abstract]
Restricted Certificates of Deposit	4. Restricted Certificates of Deposit The Company is required to maintain certain certificates of deposit (“CDs”) by a municipality in which drilling operations are located. This CD is pledged as collateral for a letter of credit issued by the Company’s bank to the municipality. The CD has a maturity date of March 8, 2017, and bears an interest rate of 0.25%. As this CD is expected to be renewed upon maturity and is not available for use in operations, it is classified as a noncurrent asset.