Oneok, Inc. is a midstream operator that provides gathering, processing, fractionation, transportation and storage services. The Company's segments include Natural Gas Gathering and Processing; Natural Gas Liquids; Natural Gas Pipelines, and Refined Products and Crude. The Natural Gas Gathering and Processing segment provides midstream services to producers in North Dakota, Montana, Wyoming, Kansas and Oklahoma. The Natural Gas Liquids segment owns and operates facilities that gather, fractionate, treat and distribute natural gas liquids (NGLs) and store Purity NGLs, primarily in Oklahoma, Kansas, Texas, New Mexico and the Rocky Mountain region, which includes the Williston, Powder River and DJ Basins. The Natural Gas Pipelines segment transports and stores natural gas. The Refined Products and Crude segment transports, stores and distributes refined products and crude oil, as well as conducts certain commodity-related activities including liquids blending and marketing activities.