Idaho Code § 70-1606
All port districts are authorized and empowered, either alone or jointly with the state of Idaho, sister states, the United States of America, or any municipal or public corporation or political subdivision thereof or with other operators of terminal or transportation facilities, to initiate and carry on the necessary engineering studies, investigations and surveys required for the proper development, improvement and utilization of all port properties, utilities and facilities, and to assemble and analyze the data thus obtained, and to make such expenditures as are necessary for such purpose, and for the proper promotion, advertising, improvement and development of the port. Port district expenditures for industrial development, port promotion, or promotional hosting shall be pursuant to specific and separate budget items as approved by the port commission as a part of its annual budget, as the same may be amended or supplemented under the provisions of this act. The port commission shall adopt written rules and regulations governing the expenditure of port funds for promotional purposes and/or port hosting by port employees and agents. Such rules and regulations shall identify the employees and agents authorized to make such expenditures and shall state the objectives of such expenditures. Port commissioners shall not seek reimbursement for any such expenditures personally made by any such commissioner, unless specific authorization for such expenditure was approved by the port commission in advance of such expenditure. Reimbursement for all such expenditures shall be upon port voucher properly identified and approved by the port commission and audited in the same manner as are other port vouchers.
Idaho Code § 70-1606