Alaska Air Group, Inc. is engaged in operating airlines. The Company operates two airlines, Alaska and Horizon. The Company also includes McGee Air Services, an aviation services provider. The Company operates through three segments: Mainline, Regional and Horizon. Its Mainline segment includes scheduled air transportation on Alaska's Boeing and Airbus jet aircraft for passengers and cargo throughout the United States, and in parts of Mexico, Costa Rica and Belize. Its Regional segment includes Horizon's and other third-party carriers scheduled air transportation for passengers across a shorter distance network within the United States and Canada under capacity purchase agreements (CPA). The Horizon segment includes the capacity sold to Alaska under a CPA. Mainline operations include Boeing 737 (B737) and Airbus A320 family (A320 and A321neo) jet service offered by Alaska. Its Regional operations consist of flights operated by Horizon and SkyWest.