Black Hills Corporation, together with its subsidiaries, operates as a diversified energy company primarily in the United States. The company’s Electric Utilities segment generates, transmits, and distributes electricity to approximately 201,500 electric customers in South Dakota, Wyoming, Colorado, and Montana, as well as distributes natural gas to approximately 34,800 natural gas utility customers in Wyoming. It owns 865 Megawatts of generation capacity and 8,496 miles of electric transmission and distribution lines. Black Hills’ Gas Utilities segment distributes natural gas to approximately 528,800 natural gas utility customers in Colorado, Nebraska, Iowa, and Kansas. It owns 624 miles of intrastate gas transmission pipelines and 19,747 miles of gas distribution mains and service lines. The company’s Oil and Gas segment engages in the exploration, development, and production of crude oil and natural gas in the Rocky Mountain region. This segment’s principal assets include the operating interests in the properties in the San Juan Basin in New Mexico and Colorado, the Powder River Basin in Wyoming, and the Piceance Basin in Colorado; and non-operated interests in wells located in the Williston, Wind River, Bear Paw Uplift, Arkoma, Anadarko, and Sacramento basins. As of December 31, 2011, it had total reserves of approximately 133 billion cubic feet equivalent of natural gas and crude oil. Black Hills’ Power Generation segment produces electric power and sells the electric capacity and energy primarily to other utilities under long-term contracts. The company’s Coal Mining segment produces coal at its coal mine near Gillette, Wyoming. Black Hills also provides appliance repair services to approximately 63,000 residential customers in Colorado, Iowa, Kansas, and Nebraska; and engages in the construction of gas infrastructure facilities for serves gas transportation customers. The company was founded in 1941 and is headquartered in Rapid City, South Dakota.