What's the difference between idea and intent？
for instance：
The idea/intent is to make more people rich.

Question

What's the difference between  idea and intent？
for instance：
 The idea/intent is to make more people rich.

Answer

In this instance, they are pretty much interchangeable. An intent is something you are directly aiming to do, while an idea is, well, an idea of something. So, in this context, "intent" sounds a bit more direct, while "idea" sounds like the outcome you are generally aiming for.

Answer

Intent is more direct. It's actually what is taken into account for the crime of murder, as opposed to negligence. So intent is a specific direct consideration for a specific result.

Idea is more like a concept. It's broader. 
This explanation applies to your sentence.
So there may be a general idea or concept to make more people rich or there may be a specific intent ( a directed action plan) to bolster and increase wealth only amongst the rich and wealthy.