LOS ANGELES — Becoming a streaming colossus is mighty expensive: Disney reported a 66 percent decline in quarterly profit on Thursday, the result of digging deep into its pockets to pay for Disney Plus, a Netflix-style movie and television service that arrives on Tuesday.

Losses in the Disney division that houses streaming totaled $740 million in the quarter, compared with a loss of $340 million in the same period last year, the company said. Wall Street was relieved it was only that much: In August, Disney had predicted losses in the $900 million range. As a result, Disney shares climbed by more than 5 percent in after-hours trading.

“We’re making a huge statement about the future of media and entertainment,” Robert A. Iger, Disney’s chief executive, said of Disney Plus during a conference call with shareholders on Thursday. The service will be dedicated to movies and shows from Disney, Pixar, the “Star Wars” franchise, National Geographic and Marvel.

Some analysts expect Disney Plus to have eight million subscribers by the end of the year and roughly 18 million by the end of 2020. Disney, no doubt wanting even more, has been running its marketing engines nonstop and offering discounts to people who enroll before the service goes live. Verizon customers can even get a year free.