MDU Resources Group Inc. is a regulated energy delivery and construction materials and services business. The Company's businesses segments are electric, natural gas distribution, pipeline, construction materials and contracting, and construction services. The electric segment generates, transmits and distributes electricity. The natural gas distribution segment distributes natural gas. The pipeline segment provides natural gas transportation and underground storage services through a regulated pipeline system primarily in the Rocky Mountain and northern Great Plains regions of the United States. The construction materials and contracting segment mines, processes and sells construction aggregates crushed stone, sand and gravel; produces and sells asphalt mix, and supplies ready-mixed concrete. The construction services segment provides inside and outside specialty contracting services in approximately 44 states plus Washington D.C.