I'm currently attending one of the highest ranked universities in the world. Cheating happens from time to time (though not often, in the last three years all the people I know who attend exams or supervise them, there was one case of cheating). If that happens they take your information and the situation is analyzed by some committee. They could in theory kick you out but if it is minor you're just gonna get a warning and the worst grade possible.

If you cheat on your thesis or on papers, that will be punished harshly. You will get your degree revoked if it was a thesis, and according to our rule book you will be kicked out and not allowed to study at the university anymore.