Oneok is a midstream service provider. Co.'s segments include: Natural Gas Gathering and Processing, which provides midstream services to producers in North Dakota, Montana, Wyoming, Kansas and Oklahoma; natural gas liquids (NGLs), which owns and operates facilities that gather, fractionate, treat and distribute NGLs and store NGL products, primarily in Oklahoma, Kansas, Texas, New Mexico and the Rocky Mountain region; and Natural Gas Pipelines, which provides transportation and storage services to end users through its wholly owned assets and its ownership interests in Northern Border Pipeline Company and Roadrunner Gas Transmission, LLC.