Bob Iger, the chief executive of Walt Disney Co., is stepping down from his day-to-day role at the company at the end of June as he approaches his 70th birthday, the company announced in a statement Monday. Mr. Iger will remain chairman.

Mr. Iger’s departure is timed to the conclusion of Disney’s $71.3 billion acquisition of many of Fox’s assets, which closed on Monday. Under Mr. Iger, Disney transformed itself into a powerhouse media company, ushering in successful adaptations of franchises like “Star Wars” and “Avatar.” For the most part, Disney under Mr. Iger — the “softer” but nonetheless wildly successful CEO of ABC — was praised as a nimble media company willing to take bold swings when warranted. But critics like Corey Levitan, writing at Salon, have railed against the growing monolith, often obsessed with global politics, and something of a dominant player in Hollywood, pulling back from production and other commitments to other areas of content creation.

He was criticized for a lukewarm response to the streaming service that is being launched by Netflix (Disney recently acknowledged that its service will lag Netflix and launch in late 2020). And he was called a megalomaniac for the lavish construction at Disney World, where an artist recently created a wonderful, if somewhat hyperbolic, drawing of what Disney World could look like after the completion of several massive plans.

But Mr. Iger seems comfortable taking a rest and a break, just after Disney’s staggering success in landing Fox. He will remain as chairman through 2021. Mr. Iger is also expected to write about issues such as media regulation and technology in a series of essays as part of the Smithsonian Institution’s publication on leadership and mentorship.

Ms. Iger, Bob’s wife of 22 years, announced the news with the following statement, thanking his many fans:

Thank you for all the continued warm wishes and wishes for my husband, Bob Iger. We’re so grateful. pic.twitter.com/rElmZEa3Uw — Nicole Iger () February 25, 2019

Her remarks will surely put a little bittersweet note in the balloon of news that Mr. Iger is stepping down at the end of June.