I understand it is pretty vague... but I am unable to give the details to just anyone. The idea is new and i dont want someone with the resources to just come along and steal it.
I understand your concerns, but if you are willing to give up the information in a personal message then those people will just message you. You aren't going to find any investors who will invest blindly into your project. If it is an original idea, then after you have released it there will be dozens of different copies out within a few weeks, which one is more successful depends on who does it better and not the original person who came up with the idea.
Please state what sort of investment you are expecting from each member, and what their other duties will be.