I don’t…get it. The whole point of a major is to build a foundation of breadth in the broad area and a little depth in one specific part of the area. Interdisciplinary studies majors sometimes circumvent that goal, but most interdisciplinary studies degrees (from what I can tell) require or allow students to build at least two concentrations (and sometimes three) in a specific area. Basically, it seems like it’s a self-constructed major - the point is still to build breadth and depth, but perhaps in an area that your college doesn’t offer or in some field that’s truly interdisciplinary (like American studies, if your college doesn’t have that - you might draw classes from history, political science, sociology, literature, and the arts, but they’d all be focused on American issues).
Like Tufts says:
A major that is truly interdisciplinary is one that represents an integration of traditional disciplines, a melding of fields that cannot be accomplished by the usual structure of a major/minor or a double major/minor. The Interdisciplinary Studies major draws on courses from at least two of the following six areas of study: humanities, arts, social sciences, natural sciences, mathematics (quantitative), and engineering…An interdisciplinary major is not a fallback or a substitute for those who cannot decide on a major…it is a serious undertaking for the student who is committed to blending disciplines in a way that is demonstrably relevant to an identifiable area of intellectual inquiry.
Given that you have almost complete flexibility to design your own major with your own concentrations, why on earth would you also need three minors? It seems to me like the most intelligent thing to do is build an interdisciplinary major that blends coursework from computer science, business, and economics in some cohesive way - like a business analytics, informatics, or operations research-type program.
If you mean that you want to make those three concentrations/areas part of your IS major, then that could potentially be good, depending on you do it. The idea is not to just major in a bunch of stuff because you can’t decide what you want to do; the idea is to be thoughtful about the ways in which these topics hang together and influence/inform each other, and craft a course of study from that blend (with help from faculty members). Computer science and business/economics actually have a lot of ways in which they work together and might be interdisciplinary, so you could make a great interdisciplinary major out of that - but it’s going to be up to you to figure out the best way to do it.