Although it's not a huge budget, it's not small, either. When I hear of an indie title, I think of a small company nobody's heard of with a bubblegum and shoelace budget. Amnesia is the first one that comes to mind. Pillars of Eternity was made by Obsidian and managed to raise, as you said, $4 mill. So I guess it's fairly indie, but it's not some unity game a Russian guy cobbled together, either.