NEW YORK - Online travel giant Expedia announced plans on Thursday to spin off TripAdvisor into a separate publicly traded company later this year. Expedia shares soared 12.68 percent to $25.35 in after-hours trading following the announcement. TripAdvisor, which was founded in 2000, provides reviews and advice on hotels, flights, vacation packages and other services. It has sites in 29 countries and its various brands attract more than 50 million unique visitors a month. The new company will be made up of TripAdvisor and its 18 other travel media and advertising brands, Expedia said. It said stock in TripAdvisor will be distributed to Expedia stockholders. Expedia said it expects the spin-off, which will need the approval of shareholders, to be completed in the third quarter of the year. Expedia purchased TripAdvisor in 2004 for $200 million.