My experience with F500 companies is that they are extremely political. This means that lots of ideas get funded without any analysis of the value. The dynamic in each company and potentially each division will be different. Ultimately you might be more successful if you can find a director level or above who can pitch it for you. At the very least you should be able to articulate the value to consumers and the compnay in a few sentences with maybe an additional one or two sentences to describe how it works. Ultimately your desire and passion to make it happen is potentially more important than the idea itself.

What people should care about: 1) target and size of market 2) alignment to current product mix/message 3) cost/risk to produce 4) how will this benefit the company

What they really care about is: 1) what am I bonused on 2) How can I get a promotion 3) How will what you are telling me help me with 1 or 2 4) Will I be embarrassed if I place a bet on you