NiSource Inc. is an energy holding company. The Company operates through two segments: Gas Distribution Operations and Electric Operations. The Gas Distribution operations, through its wholly owned subsidiary NiSource Gas Distribution Group, Inc., owns five distribution subsidiaries that provide natural gas to residential, commercial and industrial customers in Ohio, Pennsylvania, Virginia, Kentucky, and Maryland. The Company operates approximately 54,600 miles of distribution main pipeline plus the associated individual customer service lines and 1,000 miles of transmission main pipeline located in its service areas. The Electric Operations segment generates, transmits and distributes electricity, through its subsidiary NIPSCO, to approximately 486,000 customers in 20 counties in the northern part of Indiana. The Electric Operations segment is also engaged in wholesale electric and transmission transactions. The Company owns and operates sources of generation as well as source power.