Disney CEO Bob Iger, who steered the absorption of Star Wars, Marvel and Fox's entertainment businesses and the launch of a Netflix challenger, is stepping down immediately, the company said in a surprise announcement Tuesday.

The Walt Disney Co. named as his replacement Bob Chapek, most recently chairman of Disney's parks, experiences and products business.

"Did not see this coming — Wowza," tweeted LightShed media analyst Rich Greenfield.

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Iger, who turned 69 this month, will remain executive chairman through the end of his contract on December 31, 2021, the company said. Besides leading the company's board, Iger said he will spend more time on Disney's creative endeavors, including the ESPN sports network, the newly acquired Fox studios and the Hulu and Disney Plus streaming services. He said he could not do that while running Disney on a day-to-day basis.

"It was not accelerated for any particular reason other than I felt the need was now to make this change," Iger said on a conference call with reporters and analysts.

Robert Iger, chairman and CEO of Walt Disney Co., speaks during an Economic Club of New York event in Manhattan last October. Getty

Iger's most recent coup was orchestrating a $71 billion acquisition of Fox's entertainment assets in March and launching the Disney Plus streaming service in November. That service gained nearly 29 million paid subscribers in less than three months. In a statement, Iger said it was the "optimal time" for a transition.

Pivotal Research Group analyst Jeffrey Wlodarczak said Iger had implied he would stay until his contract ended in 2021.

"On the other hand, they just successfully closed the Fox deal and had an unquestionably successful launch of Disney Plus so maybe he felt earlier was better to hand off the reins," he said.

Colin Gillis, director of research at Chatham Road Partners, said the choice of Chapek seems solid because his parks division has had success.

The 60-year-old Chapek said that while he has not led television networks or streaming services, his background in consumer-oriented businesses should help. Chapek and Iger both stressed that Disney would continue to follow the direction it had been.

Iger became chief executive of Disney in 2005 after a shareholder revolt by Roy E. Disney led to the ouster of longtime chief Michael Eisner. Iger steered Disney through successful acquisitions of Lucasfilms, Marvel, Pixar and other brands that became big moneymakers for Disney.

Iger, a former weatherman, joined broadcaster ABC in 1974, 22 years before Disney bought the network.

At ABC, Iger developed such successful programs as "Home Improvement," "The Drew Carey Show," and "America's Funniest Home Videos" and was instrumental in launching the quiz show "Who Wants to Be a Millionaire." He was also criticized for cancelling well-regarded but expensive shows such as "Twin Peaks," "China Beach" and "thirtysomething."

Iger's appointment as CEO had been accompanied by controversy and protest from dissident shareholders Roy E. Disney and Stanley Gold. But he has come to be seen as a golden-boy top executive, and even someone who could run for president.

Iger was the second-highest paid CEO in 2018, as calculated by The Associated Press and Equilar, an executive data firm. He earned $65.6 million. The top earner was Discovery's David Zaslav who earned $129.5 million.

Susan Arnold, the independent lead director of the Disney board, said succession planning had been ongoing for several years.

Chapek is only the seventh CEO in Disney history. Chapek was head of the parks, experiences and products division since it was created in 2018. He was previously head of parks and resorts and before that president of consumer products.