onChange instead of keyup

Hello,

I am using CKeditor 3.2 with Jquery in the new CMS that i'm building.

I have build a function that realtimeupdate all the changes into a example field, so that the user can precise see how the final output will be, including the surrounding content and CSS.
This works perfect, al the content typed into the editor is updated directly into the example.

For this function i used the keyup event.

Now i noticed that when i make a change in de the editor with the toolbar, by example the font size, the keyup event isn't fired becourse the user isn't typing in the editor.

Is there an other way or function to also fire an event when those changes are made?
Maybe a kind of onChange function?

Thanks, Joost