Nope. An idea is just a piece of the whole picture. Take the wildly successful Halflife game series: You're a scientist with a crowbar in a underground labratory overrun with aliens and soldiers trying to kill you. Many other games already had that "idea", but Halflife's gold was how it was executed.
You think that even if the idea is unique (and I mean really unique) - nobody will want it only because "It is just an idea?"
I mean, isn't it all (games, novels, movies, etc.) just and only about the prime idea and the rest (the actual work - programming, art, music, sound effects, etc.) can only "boost" or "kill" the quality?
Take World of Warcraft: You are in a fantasy world. With orcs and Elves. And you have swords and magic. And it's online. Sound like every other MMO out there? Yep, but they executed it way better then their competitors at the time of their launch.
Modern Warfare: Have guns, shoot other players. Billion dollar franchise. Because of quality, not idea.
Halo: Have guns, shoot other players. In SPACE! With aliens! Billion dollar franchise. Because of quality, not idea.
Mario: Consistently high level of quality = long term success. Billion dollar franchise.
Spyro the Dragon*: High level quality degraded over time = No longer much of a success.
Banjo Kazooie: High level quality, degraded over time = No longer much of a success.
Sonic the Hedgehog: High level quality, degraded over time = No longer much of a success.
What is the difference between Mario, Spyro, Banjo Kazooie, and Sonic? The level of polish put into each title.
*Spyro recently was rebooted as a new franchise by a new company using new mechanics, and is currently really successful. The reason why it had to be rebooted and revived is because the old franchise (which is what I was referring to above) was a dead beaten horse from lack of quality games in the series after the original two or three games were followed by several low quality sequels.
An idea on it's own can be great (Tetris! Rubik's cube!). But an idea on it's own doesn't mean it will be great. Angry Birds is nothing new; but its execution made Rovio millions. In indie games Braid is nothing new (not even the time mechanic), but its high level of polish made it very successful (also made millions). Sure, sometimes there are flukes like Minecraft that became wildly successful despite not being new OR highly polished, but that's not the norm.
The elbow grease put into something is actually more important than the idea itself. Sure, you can't polish junk... but there are loads and loads of non-junk ideas that you can polish. If I'm going to provide the polish, and I need an idea, while will I pay you for your "awesome unique idea" (in your biased opinion), when I have my own "awesome unique ideas" (in my biased opinion), or I can find thousands of great ideas just laying about?
The polish makes the game, the idea is what starts the game. Seeds are cheap. Farming the seeds for 9 months before harvest, the nutrients in the ground, and the rain, is what makes the seeds into wheat. Then the work of grinding the wheat into flour, and then baking the flour into bread, is what makes actual food. So no, most people won't pay you for your seeds. We'd be happy to teach you how to farm, however, so you can grow your seeds into your own wheat.
I'm not saying your idea isn't great - but I am saying your idea as long as it is just 'an idea' is worth nothing. What it produces could be worth alot, but it's the process of producing it that costs the money - there are many ideas that could be worth alot.
Further, many people think having an idea is game design. Or writing a plot is game design. Or creating levels is game design. Game design is designing gameplay mechanics and iterating over them and tweaking them and balancing them. Writing plot is writing plot, creating characters is creating characters, designing worlds is designing worlds, designing gameplay is game design. It's all part of game development.
I don't want to be a game-play mechanic designer. I want to be a world crafter. What part of making games (game development) is the part that actually interests you? Hone your skills in that area (and mess about in other areas to round yourself out), and pursue a career there.
If an idea pops into your head, and you enjoy expanding on it and playing with and developing that idea for a few weeks, do you really expect to be able to turn around and sell the idea?
We all think the part of the game we work on is the most important part - because we're passionate about it. But no, an idea is not the majority of, nor the most important part, of a game. Not commercially successful billion dollar games, and not high quality in-it-for-the-art indie games. High quality games come from the "high quality" part - the effort and refinement and repeated applications of polish over an already stable foundation. An idea is part of the foundation, yes, but not the only part and not the largest part. And a good game without polish is almost (but not quite) as bad as a bad game with polish.
100 million dollars to make an AAA game is on the low side of things. (And marketing is probably triple that)
Additionally, Isn't a good GDD also the part of the overall work on the game? I spent hundreds of hours writing my GDD and its now more then 4000 pages.
Also, it contains the story script, art concept and notes for the music.
And of course, I can go with much less then 50% of the profits. Why it cant have at least a minimum chance to succeed?
100+ people working on it full time for 18 or more months is normal for a triple-A game.
The profits (a gamble or investment) go to the people putting in the money to bankroll the whole thing. The salary (regardless of the success of the game) goes to the people putting in the work. Even 1% of the profits would be too ridiculous. If a game made 200 million, you want 2 million for your hundreds of hours? Let's say you spent over 200 hours on the design document, and want 1% of the 200 million profit. Your time is really worth $10,000 an hour salary?
Your 200 hours deserves more recognition or payment than (50 hours a week for 50 weeks in a year for a year and a half) 3750 hours of every single other person working on the game? I know you aren't saying that, but I'm trying to show (through extreme comparisons) why it just doesn't make sense.
Game studios have full time game-play mechanic designers working on their games, and full time art designers, level designers, character designers, sound designers, music composers, writers, artists, 3d modelling, etc... working on their games.
My advice: Find what actually interests you, and pursue it, and either go independent with it, or pursue a career in it.
When I say 'what interests you', I don't mean "game development", I mean find what part(s) of game development interests you the most.
You made something in your spare time, that you enjoyed working on: Awesome! You don't have the funding or the skills (programming, 2D art, 3D modelling, music composing, etc...) to actually make it into a game: That really sucks, and I know how that feels.
So: Why not learn the neccesary skills to actually make it, by investing your time (which you have plenty of) and converting your 'time' resources into 'skill' resources? You can then use your 'skills' to operate on your 'ideas' to produce 'moneys'. But first, you have to get those skills.
It takes an average of 10,000 hours to master a subject supposedly. If you start learning to program now, or make art now, or write now, in 6 or 7 years you'll be really really good at it - if you actually enjoy doing it. Many people will say, "6 or 7 years? Forget that!", and six or seven years later, they'll be just as inexperienced as they are now, and working a lame job they don't like. The effort of those 6 or 7 years in pursuing what you enjoy doing is what will get you a salary or a share of profits. Not the 200 (or 2000) hours you put in for fun doing something that you wanted to do.
I'll let you in on a secret: If you find what part of game development you really actually love, and you really set out to hone your craft, you'll find out that you'd enjoy the craft more than your ideas. For me, I love world design (creativity) and I love programming (more scientific). I only got into programming as a means to get to craft worlds, but after the first two years, I suddenly realized that I actually enjoy programming in and of itself, just as much or maybe even more than crafting worlds. As I pursued several other skills to allow me to craft worlds, some I find out I enjoy, others I find out I'm indifferent to or not particularly fond of.
Go make some (small) games! And try your hands at a hundred different things (scripting, programming, character design, writing, animation, 3D modelling, concept art, composing, ambient sound design, level layout, testing, etc...), and see which ones fit your taste buds. Then gone hone your craft in two or three of them, really focusing on them, over the next decade. The "next decade" may sound depressing, but not when you realize how fun these things can be if they are the ones you enjoy. But until you start enjoying them, anything that denies you instant gratification will make you want to throw up you hands, say "forget it", and walk away.
Here ends a rambling post written too late at night.