Did the Germans in Nazi Germany Know what was happening to the Jews?

I used to live in Germany,  and I love the German people this article isn’t about hating Germans.
I have been reading the Nuremberg Trial. One thing I have been noticing in it again and again it that the leaders of the NAZI movement continually claimed that they did not know just how badly the Jews were being treated. I have also heard others claim that the common citizens did not know either. My question is how could they not know that something was rotten?
During the Night of Broken Glass 30 thousand Jews were victimized, and that was just one night at the beginning. How could one not notice that so many people that you used to see daily were gone? Anyone with eyes and ears should have known that something was wrong, even if they did not know just how bad it was. In fact many people did know, some of my greatest heroes are people that during that time risked their lives fighting the evils that went on during those dark days.
Were the good elderly people that I met in Germany hiding a very deep dark side? I don’t think they were evil I think their minds had trouble believing that anyone could really be as evil as people like Hitler were. Even today we fall into this trap. Every time we catch a serial killer or a child rapist, or some one who commits a great evil there are people who stand up to say they don’t believe that the person did anything wrong even with clear evidence that they did.
We don’t want to believe it so we don’t. We don’t want to believe that there are people who are willing to kill babies for a living so we simply doubt that the thing inside a human woman is a human baby.
If you are a Christian you are supposed to be the light of the world. You must fight this impulse to only see the good in folk, and call out the evil you see. But unlike the world when we judge we are supposed to do it with as much love as possible. If loving the person doing the evil is impossible for you do it because you love the victims and you want to prevent any more victims from getting hurt.