Contingencies	9 Months Ended
Contingencies	Sep. 30, 2020
Commitments and Contingencies Disclosure [Abstract]
Contingencies	Contingencies This note should be read in conjunction with the complete description under Item 15 — Note 17, Commitments and Contingencies, to the Company's 2019 Form 10-K. Contingencies The Company's material legal proceedings are described below. The Company believes that it has valid defenses to these legal proceedings and intends to defend them vigorously. The Company records reserves for estimated losses from contingencies when information available indicates that a loss is probable and the amount of the loss, or range of loss, can be reasonably estimated. As applicable, the Company has established an adequate reserve for the matters discussed below. In addition, legal costs are expensed as incurred. Management assesses such matters based on current information and makes a judgment concerning its potential outcome, considering the nature of the claim, the amount and nature of damages sought, and the probability of success. The Company is unable to predict the outcome of the legal proceedings below or reasonably estimate the scope or amount of any associated costs and potential liabilities. As additional information becomes available, management adjusts its assessment and estimates of such contingencies accordingly. Because litigation is subject to inherent uncertainties and unfavorable rulings or developments, it is possible that the ultimate resolution of the Company's liabilities and contingencies could be at amounts that are different from its currently recorded reserves and that such difference could be material. In addition to the legal proceedings noted below, the Company and its subsidiaries are party to other litigation or legal proceedings arising in the ordinary course of business. In management's opinion, the disposition of these ordinary course matters will not materially adversely affect the Company's consolidated financial position, results of operations, or cash flows. Nebraska Public Power District Litigation On January 11, 2019, Nebraska Public Power District, or NPPD, sent written notice to certain of the Company’s subsidiaries which own the Laredo Ridge and Elkhorn Ridge wind projects alleging an event of default under each of the PPAs between NPPD and the projects. NPPD alleges that the Company moved forward with certain transactions without obtaining the consent of NPPD. NPPD threatened to terminate the applicable PPAs by February 11, 2019 if the alleged default was not cured. The Company filed a motion for a temporary restraining order and preliminary injunction in the U.S. District Court for the District of Nebraska relating to the Laredo Ridge project, and a similar motion in the District Court of Knox County, Nebraska for the Elkhorn Ridge project, to enjoin NPPD from taking any actions related to the PPAs. On February 19, 2019, the U.S. District Court in the Laredo Ridge matter approved a stipulation between the parties to provide for an injunction preventing NPPD from terminating the PPA pending disposition of the litigation. On February 26, 2019, the Knox County District Court approved a similar stipulation relating to the Elkhorn Ridge project. On April 13, 2020, the U.S. District Court granted the wind projects' motion for summary judgment and permanently enjoined NPPD from terminating the PPAs in reliance on the alleged events of default. The U.S. District Court decision was appealed by NPPD on May 11, 2020 and the case in the Knox County District Court remains pending, but has been stayed pending the outcome of the U.S. District Court case. The Company believes the allegations of NPPD are meritless and the Company is vigorously defending its rights under the PPAs. Buckthorn Solar Litigation On October 8, 2019, the City of Georgetown, Texas, or Georgetown, filed a petition in the District Court of Williamson County, Texas naming Buckthorn Westex, LLC, the Company’s subsidiary that owns the Buckthorn Westex solar project, as the defendant, alleging fraud by nondisclosure and breach of contract in connection with the project and the PPA, and seeking (i) rescission and/or cancellation of the PPA, (ii) declaratory judgment that the alleged breaches constitute an event of default under the PPA entitling Georgetown to terminate, and (iii) recovery of all damages, costs of court, and attorneys’ fees. On November 15, 2019, Buckthorn Westex filed an original answer and counterclaims (i) denying Georgetown’s claims, (ii) alleging Georgetown has breached its contracts with Buckthorn Westex by failing to pay amounts due, and (iii) seeking relief in the form of (x) declaratory judgment that Georgetown’s alleged failure to pay amounts due constitute breaches of and an event of default under the PPA and that Buckthorn did not commit any events of default under the PPA, (y) recovery of costs, expenses, interest, and attorneys’ fees, and (z) such other relief to which it is entitled at law or in equity. Buckthorn Westex believes the allegations of Georgetown are meritless, and Buckthorn Westex is vigorously defending its rights under the PPA.