Midwest Airlines and Northwest Airlines formalized their plans for a codeshare partnership

, covering 250 routes and 1,000 flights. Initial cooperation will include Midwest flights from Milwaukee, Kansas City and Omaha to the West Coast, and Northwest flights to Hawaii. Midwest parent Midwest Air Group last month agreed to be acquired by TPG Capital, with financing from Northwest, which said it would become "a passive investor." Bizjournals.comreported that Northwest's stake would be 47 percent after the transaction closes.