Commitments and Contingencies	6 Months Ended
Jun. 30, 2015
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Included below is a discussion of various future commitments of the Company as of June 30, 2015. The commitments under these arrangements are not recorded in the accompanying Condensed Consolidated Balance Sheet. The amounts disclosed represent undiscounted cash flows on a gross basis, and no inflation elements have been applied. Lease obligations. The Company’s total rental commitments under leases for office space and other property and equipment at June 30, 2015 were $30.7 million. Drilling contracts. As a result of its lowered 2015 capital expenditure program, the Company elected to early terminate certain drilling rig contracts and recorded rig termination expense of $2.8 million and $3.9 million in its Condensed Consolidated Statement of Operations for the three and six months ended June 30, 2015, respectively. The Company did not elect to early terminate any drilling rig contracts during the six months ended June 30, 2014. As of June 30, 2015, the Company had certain drilling rig contracts with initial terms greater than one year. In the event of early termination under these contracts, the Company would be obligated to pay approximately $8.5 million as of June 30, 2015 for the days remaining through the end of the primary terms of the contracts. Volume commitment agreements. As of June 30, 2015, the Company had certain agreements with an aggregate requirement to deliver a minimum quantity of approximately 30.2 MMBbl and 5.3 Bcf, prior to any applicable volume credits, from its Williston Basin project area within specified timeframes, all of which are less than ten years. Future commitments under these agreements were approximately $185.6 million as of June 30, 2015. Purchase agreements. As of June 30, 2015, the Company had certain agreements for the purchase of fresh water with an aggregate future commitment of approximately $38.9 million. Cost sharing agreements. As of June 30, 2015, the Company had certain agreements to share the cost to construct and install electrical facilities. The Company’s estimated future commitment under these agreements was $4.5 million as of June 30, 2015. Litigation. The Company is party to various legal and/or regulatory proceedings from time to time arising in the ordinary course of business. While the ultimate outcome and impact to the Company cannot be predicted with certainty, the Company believes that all such matters are without merit and involve amounts which, if resolved unfavorably, either individually or in the aggregate, will not have a material adverse effect on its financial condition, results of operations or cash flows. When the Company determines that a loss is probable of occurring and is reasonably estimable, the Company accrues an undiscounted liability for such contingencies based on its best estimate using information available at the time. The Company discloses contingencies where an adverse outcome may be material, or in the judgment of management, the matter should otherwise be disclosed. On July 6, 2013, a freight train operated by Montreal, Maine and Atlantic Railway (“MMA”) carrying crude oil (the “Train”) derailed in Lac-Mégantic, Quebec. In March 2014, Oasis Petroleum Inc. and OP LLC were added to a group of over fifty named defendants, including other crude oil producers as well as the Canadian Pacific Railway, MMA and certain of its affiliates, owners and transloaders of the crude oil carried by the Train, several lessors of tank cars, and the Attorney General of Canada, in a motion filed in Quebec Superior Court to authorize a class-action lawsuit seeking economic, compensatory and punitive damages, as well as costs for claims arising out of the derailment of the Train (Yannick Gagne, etc., et al. v. Rail World, Inc., etc., et al., Case No. 48006000001132) (the “Class-Action”). The motion generally alleges wrongful death and negligence in the failure to provide for the proper and safe transportation of crude oil. The Company believes that all claims against Oasis Petroleum Inc. and OP LLC in connection with the derailment of the Train in Lac-Mégantic, Quebec are without merit. On August 7, 2013, MMA filed for bankruptcy protection in the Quebec Superior Court and the United States Bankruptcy Court in Bangor, Maine (together, the “Bankruptcy Actions”). The trustees appointed in the Bankruptcy Actions have negotiated settlement agreements with the majority of the named defendants in the Class-Action, including Oasis Petroleum Inc. and OP LLC. The Quebec Superior Court has approved the settlement agreement which was pending before it, but such approval is subject to appeal. The second settlement agreement remains pending before the United States Bankruptcy Court in Bangor, Maine. If approved, pursuant to the settlement agreements, Oasis Petroleum Inc. and OP LLC have agreed to contribute to the compensation fund established for those suffering losses as a result of the Lac-Megantic derailment. The Company has determined that such contributions are fully covered by the Company’s insurance policies. Furthermore, the settlement agreements would bar future litigation against Oasis Petroleum Inc. and OP LLC in Canada and the United States arising out of the Lac-Megantic derailment.

Commitments and Contingencies

Included below is a discussion of various future commitments of the Company as of June 30, 2015. The commitments under these arrangements are not recorded in the accompanying Condensed Consolidated Balance Sheet. The amounts disclosed represent undiscounted cash flows on a gross basis, and no inflation elements have been applied.

Lease obligations. The Company’s total rental commitments under leases for office space and other property and equipment at June 30, 2015 were $30.7 million.

Drilling contracts. As a result of its lowered 2015 capital expenditure program, the Company elected to early terminate certain drilling rig contracts and recorded rig termination expense of $2.8 million and $3.9 million in its Condensed Consolidated Statement of Operations for the three and six months ended June 30, 2015, respectively. The Company did not elect to early terminate any drilling rig contracts during the six months ended June 30, 2014.

As of June 30, 2015, the Company had certain drilling rig contracts with initial terms greater than one year. In the event of early termination under these contracts, the Company would be obligated to pay approximately $8.5 million as of June 30, 2015 for the days remaining through the end of the primary terms of the contracts.

Volume commitment agreements. As of June 30, 2015, the Company had certain agreements with an aggregate requirement to deliver a minimum quantity of approximately 30.2 MMBbl and 5.3 Bcf, prior to any applicable volume credits, from its Williston Basin project area within specified timeframes, all of which are less than ten years. Future commitments under these agreements were approximately $185.6 million as of June 30, 2015.

Purchase agreements. As of June 30, 2015, the Company had certain agreements for the purchase of fresh water with an aggregate future commitment of approximately $38.9 million.

Cost sharing agreements. As of June 30, 2015, the Company had certain agreements to share the cost to construct and install electrical facilities. The Company’s estimated future commitment under these agreements was $4.5 million as of June 30, 2015.

Litigation. The Company is party to various legal and/or regulatory proceedings from time to time arising in the ordinary course of business. While the ultimate outcome and impact to the Company cannot be predicted with certainty, the Company believes that all such matters are without merit and involve amounts which, if resolved unfavorably, either individually or in the aggregate, will not have a material adverse effect on its financial condition, results of operations or cash flows. When the Company determines that a loss is probable of occurring and is reasonably estimable, the Company accrues an undiscounted liability for such contingencies based on its best estimate using information available at the time. The Company discloses contingencies where an adverse outcome may be material, or in the judgment of management, the matter should otherwise be disclosed.

On July 6, 2013, a freight train operated by Montreal, Maine and Atlantic Railway (“MMA”) carrying crude oil (the “Train”) derailed in Lac-Mégantic, Quebec. In March 2014, Oasis Petroleum Inc. and OP LLC were added to a group of over fifty named defendants, including other crude oil producers as well as the Canadian Pacific Railway, MMA and certain of its affiliates, owners and transloaders of the crude oil carried by the Train, several lessors of tank cars, and the Attorney General of Canada, in a motion filed in Quebec Superior Court to authorize a class-action lawsuit seeking economic, compensatory and punitive damages, as well as costs for claims arising out of the derailment of the Train (Yannick Gagne, etc., et al. v. Rail World, Inc., etc., et al., Case No. 48006000001132) (the “Class-Action”). The motion generally alleges wrongful death and negligence in the failure to provide for the proper and safe transportation of crude oil. The Company believes that all claims against Oasis Petroleum Inc. and OP LLC in connection with the derailment of the Train in Lac-Mégantic, Quebec are without merit.

On August 7, 2013, MMA filed for bankruptcy protection in the Quebec Superior Court and the United States Bankruptcy Court in Bangor, Maine (together, the “Bankruptcy Actions”). The trustees appointed in the Bankruptcy Actions have negotiated settlement agreements with the majority of the named defendants in the Class-Action, including Oasis Petroleum Inc. and OP LLC. The Quebec Superior Court has approved the settlement agreement which was pending before it, but such approval is subject to appeal. The second settlement agreement remains pending before the United States Bankruptcy Court in Bangor, Maine. If approved, pursuant to the settlement agreements, Oasis Petroleum Inc. and OP LLC have agreed to contribute to the compensation fund established for those suffering losses as a result of the Lac-Megantic derailment. The Company has determined that such contributions are fully covered by the Company’s insurance policies. Furthermore, the settlement agreements would bar future litigation against Oasis Petroleum Inc. and OP LLC in Canada and the United States arising out of the Lac-Megantic derailment.