$2.15 billion
You were close enough though, IMO. This obviously is production budgets alone since they never report marketing budgets and there are other factors such as product placement and other things that can offset the costs by a considerable margin but those are rarely reported either. So using the standard 2X of the production budget to get into the black, after $4.3 billion all the rest is basically profit. Figuring that a ballpark of $9.1 billion will be where they are at when Ant-Man is completely tapped out, that Disney should have covered the $4 billion they bought Marvel for already and be a few hundred million $ in the black already with everything else from here on out simply adding to that black in their ledger.
https://en.wikipedia.org/wiki/List_of_Marvel_Cinematic_Universe_films#Box_office_performance
And this Fortune magazine article from about a week ago(10/08/2015) has further interesting things to say:
http://fortune.com/2015/10/08/disney-marvel/
We tend to forget that they are making money on more than just whatever box office the movies bring in.