If its a GREAT idea, it deserves to nurtured, protected, and sheltered from those that steal GREAT ideas, and even useless ideas.
If its a great idea, I suggest you consult an intellectual property attorney.
Venture capitalists are among the most unscrupulous scoundrels on the planet.
I say that as an attorney, and the adage that it takes one to know one.
Showing an idea to any VC speculator without certain protections and safeguards is beyond nuts.