"The idea of God exists ever since the beginning of humankind. You go to any part of the world, and you will encounter some form or idea of God. And even though, their views of God may be world apart, it conveys the universal belief in the existence of God."Because, well... no. That's really not right. And it ties in to something I was starting to say over at Gullible's Travels a couple of months ago, so I guess this is my chance to finally finish expressing that thought.
If there's one thing I learned while getting a Minor in Anthropology, it's that "universal beliefs"... aren't.
"The idea of God exists ever since the beginning of humankind."
No, it hasn't - not the way you mean it, anyway. The idea of God traces back from Christianity and Islam to Judaism, which is to say that it comes from a particular tribe in a particular area of the world. The fact that the concept went viral and is now ubiquitous does not change the fact that it was originally a tribal and parochial view of the divine.
I am neither Jewish nor a religious scholar, so offhand I don't have any good scholarly citations to support this. (If you do, feel free to add them in the comments. Hell, if you've got conflicting citations, feel free to add those in the comments as well.) But my understanding is that early Judaism wasn't even monotheistic in the sense that we think of it today. Instead, they were monolatrous (or henotheistic) - that is, they acknowledged the existence of other gods, but they only worshiped one.
The "idea of God" has a very specific history relating to specific human cultures during specific time periods in specific areas of the world. It isn't something that's always been around.
You go to any part of the world, and you will encounter some form or idea of God.
This one is... not true, but sort of vaguely off in the right direction. What you'll find, actually, is that anywhere there are people there is some sort of religion (also, some form of art). Where it breaks down is the idea that this constitutes "some form or idea of God." It doesn't. It's not even close.
Religion, like Art, is a tricky thing to define. For our purposes here, I'm going to define it as "a belief in the unseen forces that shape our lives." I'm told that people engaged in the study of comparative religions break beliefs down into four or five basic categories: Monotheistic (one deity), Dualistic (two deities), polytheistic (many deities), and pantheistic (the Divine spread through the world) - plus, possibly, shamanic, where the Divine exists in specific places, objects, animals, etc. Apparently shamanic religions are sometimes considered a subset of pantheistic religions, though personally I think that's a mistake.
And even though, their views of God may be world apart, it conveys the universal belief in the existence of God.
And again: no. No, it doesn't. There's far, far too much variety for that. In fact, the views you find are so irredeemably far apart, that they don't convey the universal belief in much of anything.
You'd be on far safer ground if you'd said that it conveys the universal belief that objects have their own personalities and deceased ancestors wish to be remembered. Because if you leave people to their own devices, those are the sorts of beliefs they tend to come up with. But again, that's not even remotely universal. Common, yes; universal, no.
From a historical and/or anthropological viewpoint, Christianity - and monotheism in general - is deeply weird. I mean, the transition sort of makes sense: This god is the strongest to We will only worship this god to There is only one real God, and he talks to us. But as compelling a vision of the Divine as that is, there are quite a number of things - and the Problem of Evil is chief among them - that are far easier to explain if you allow for two opposing gods; or for many gods, each with their own area of influence. 
So if you're looking through World Religions or religious history for evidence to support the Christian view of God - even among people who haven't directly heard of Him - give up now. It just isn't there.
 I like this definition because it allows me to include any sort of religious belief or practice that I've ever heard of, but still allows me to exclude atheism.
 I'd actually refer to this as animistic rather than shamanic, but that's probably only interesting to people who are curious about how the perspective of Comparative Religion folks differs from the perspective of Anthropology folks. In other words, the only people likely to care... are Sociology Majors.
 Which is, I think, a large part of the reason why Christianity goes back and forth on the existence of Satan, how much power he has relative to God, and why God doesn't do anything about it.