Commitments and Contingencies	6 Months Ended
Commitments and Contingencies	Jun. 30, 2022
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Commitments Ashtabula III Purchase. On June 23, 2022, OTP exercised its option to acquire the Ashtabula III wind farm, a 62.4 megawatt wind farm located in eastern North Dakota, for $49.7 million, subject to certain closing adjustments. Since 2013, OTP has purchased the wind-generated electricity from the Ashtabula III wind farm pursuant to a purchase power agreement, and that agreement granted OTP the option to purchase the wind farm. The purchase is subject to certain customary closing conditions and regulatory approval. We anticipate the transaction will close in January 2023. Contingencies FERC ROE. In November 2013 and February 2015, customers filed complaints with the Federal Energy Regulatory Commission (FERC) seeking to reduce the return on equity (ROE) component of the transmission rates that Midcontinent Independent System Operator, Inc. (MISO) transmission owners, including OTP, may collect under the MISO tariff rate. FERC's most recent order, issued on November 19, 2020, adopted a revised ROE methodology and set the base ROE at 10.02% (10.52% with an adder) effective for the fifteen-month period from November 2013 to February 2015 and on a prospective basis beginning in September 2016. The order also dismissed any complaints covering the period from February 2015 to May 2016. The November 2020 opinion is subject to judicial review. We have deferred recognition and recorded a refund liability of $2.5 million as of June 30, 2022. This refund liability reflects our best estimate of required refunds to customers once all regulatory and judicial proceedings are completed. Regional Haze Rule (RHR). The RHR was adopted in an effort to improve visibility in national parks and wilderness areas. The RHR requires states, in coordination with the Environmental Protection Agency (EPA) and other governmental agencies, to develop and implement plans to achieve natural visibility conditions. The second RHR implementation period covers the years 2018-2028. States are required to submit a state implementation plan to assess reasonable progress with the RHR and determine what additional emission reductions are appropriate, if any. Coyote Station, OTP's jointly owned coal-fired power plant in North Dakota, is subject to assessment in the second implementation period under the North Dakota state implementation plan. The North Dakota Department of Environmental Quality (NDDEQ) has published a draft of its state implementation plan for public comment and held a public information session regarding the proposed plan. The draft plan concluded it is not reasonable to require additional emission controls during this planning period. The EPA has provided comments on the draft North Dakota state implementation plan in which it expressed disagreement with the NDDEQ's recommendation to forgo additional emission controls and has indicated that the current plan is not likely to be accepted. We anticipate the NDDEQ will file their proposed plan to the EPA for approval in August 2022. We cannot predict with certainty the impact the state implementation plan may have on our business until the state implementation plan has been approved or otherwise acted on by the EPA. However, significant emission control investments could be required and the recovery of such costs from customers would require regulatory approval. Alternatively, investments in emission control equipment may prove to be uneconomic and result in the early retirement of or the sale of our interest in Coyote Station, subject to regulatory approval. We cannot estimate the ultimate financial effects such a retirement or sale may have on our consolidated operating results, financial position or cash flows, but such amounts could be material and the recovery of such costs in rates would be subject to regulatory approval. Other Contingencies. We are party to litigation and regulatory matters arising in the normal course of business. We regularly analyze relevant information and, as necessary, estimate and record accrued liabilities for legal, regulatory enforcement and other matters in which a loss is probable of occurring and can be reasonably estimated. We believe the effect on our consolidated operating results, financial position and cash flows, if any, for the disposition of all matters pending as of June 30, 2022, other than those discussed above, will not be material.