Disney's company started to diversify, producing live-action feature films beginning with "Treasure Island" (1950) and nature documentaries, the first of which being "Seal Island" (1948). As a result, Walt Disney was needed on several different units at one time and was spending less time on animation. In 1951, he released "Alice in Wonderland", a project he had been working on since the late 1930s, though it was shelved during the war. "Alice in Wonderland" was initially moderately successful and received mixed reviews from the critics. A few decades later, the film would be hailed as one of Disney's greatest classics, making millions in subsequent theatrical and home video releases. In 1953, he released "Peter Pan", which, like "Alice in Wonderland", had been in production since the late 1930s/early 1940s and was shelved during the war. However unlike "Alice", "Peter Pan" was a big success both critically and financially on its first release.