MDU Resources Group, Inc. is a diversified natural resource company. Montana-Dakota Utilities Co. (Montana-Dakota) is a public utility division of the Company. The Company’s segments include electric, pipeline and energy services, exploration and production, construction materials and contracting and construction services. The electric segment generates, transmits and distributes electricity. The natural gas distribution segment distributes natural gas. The exploration and production segment is engaged in oil and natural gas acquisition, exploration, development and production activities. The construction materials and contracting segment mines aggregates and markets crushed stone, sand, gravel and related construction materials. The construction services segment specializes in constructing and maintaining electric and communication lines, gas pipelines, fire suppression systems, and external lighting and traffic signalization equipment.