Alaska Air Group, Inc. is a holding company of Alaska Airlines, Inc. (Alaska) and Horizon Air Industries, Inc. (Horizon), which together with its partner regional airlines, serve 95 cities through an expansive network in Alaska, the Lower 48, Hawaii, Canada and Mexico. The Company operates two airlines: Alaska Airlines and Horizon Air. The Company operates in three segments: Alaska Mainline, Alaska Regional and Horizon. Alaska Mainline is the Boeing 737 part of Alaska's business. Alaska Regional is Alaska's shorter distance network. Horizon operates regional aircraft. During the year ended December 31, 2012, the Company carried 26 million passengers. Alaska operates a fleet of passenger jets (mainline) and contracts with Horizon, SkyWest Airlines, Inc. (SkyWest) and Peninsula Airways, Inc. (PenAir) for regional capacity under, which Alaska receives all passenger revenue from those flights. Horizon operates a fleet of turboprop aircraft and sells all of its capacity to Alaska.