The Terminator made a crapton of money. It wasn't just in the box office gross, but the fact that the movie still plays rather often today on TV. That means royalties. They made video games, arcade games, comic books and toys from the 1st and 2nd movies, which also means a lot of residual income. May not be able to track it, but think about how often you see DVDs and such available. They're there because they still sell.
I'd imagine that T-1 has probably made around $500m or greater just in royalties, ect.
Back from the dead, I'm afraid.