Idaho Code § 61-524
The commission shall have power to establish a system of accounts to be kept by the public utilities subject to its jurisdiction, or to classify said public utilities and to establish a system of accounts for each class and to prescribe the manner in which such accounts shall be kept: provided, that the system of accounts to be kept by railroad corporations and common carriers shall conform to the rules and requirements of the interstate commerce commission in all respects. It may also in its discretion prescribe the forms of accounts, records and memoranda to be kept by such public utilities, including the accounts, records and memoranda of the movement of traffic as well as the receipts and expenditures of moneys, and any other forms, records and memoranda which in the judgment of the commission may be necessary to carry out any of the provisions of this act.
The systems of accounts established by the commission and the forms of accounts, records and memoranda prescribed by it shall not be inconsistent, in the case of corporations subject to the provisions of the act of congress entitled "An act to regulate commerce," approved February 4, 1887, and the acts amendatory thereto, with the systems and forms from time to time established for such corporations by the interstate commerce commission.
Where the commission has prescribed the forms of accounts, records or memoranda to be kept by any public utility not subject to the provisions of the act of congress entitled "An act to regulate commerce," approved February 4, 1887, and the acts amendatory thereto, for any of its business, it shall thereafter be unlawful for such public utility to keep any accounts, records or memoranda for such business other than those so prescribed, or those prescribed by or under the authority of any other state or of the United States, excepting such accounts, records or memoranda as shall be explanatory of and supplemental to the accounts, records or memoranda prescribed by the commission.
Idaho Code § 61-524