The agreement, which was announced in December, is now working its way through the regulatory process and is still on track to take about 12 to 18 months to complete, Iger said in an interview with "Closing Bell."
"We spent the last 6 weeks or so learning more about their businesses," he said. "I've been meeting with their senior executives, and I'll say that knowing what we know now, we are even more encouraged by the assets that we're buying and the talent that comes with it."
If the acquisition is approved, Disney will get Fox's movie studios, networks Nat Geo and FX, Star TV, and stakes in Hulu, Sky and Endemol Shine Group, as well as regional sports networks.
On Tuesday, Disney reported quarterly earnings that beat expectations, but revenue missed estimates.
Its adjusted EPS came in at $1.89 versus $1.61 expected by analysts, according to Thomson Reuters. It reported revenue of $15.35 billion. Wall Street analysts were anticipating $15.45 billion in revenue, according to Thomson Reuters.
That adjusted earnings per share figure accounts for the recent tax overhaul and other one-time benefits totaling about $1.6 billion.
In addition to that one-time tax benefit and previously announced $1,000 employee bonuses, Iger told CNBC the new tax law will also free up more free cash flow for the company. That will allow it to continue investing, he added.
"You'll see a blend of investment going forward that will be somewhat similar to the way we've been investing before," he said, pointing to the company's track record of investing in organic growth.
However, the size of the Fox acquisition "suggests that we won't be acquiring anything at least of any significance for quite a long period of time."
— CNBC's Christine Wang and Michelle Castillo contributed to this report.