CKEDITOR.instances.insert_desc.setData( CKEDITOR.instances.body.getData());
var editor = CKEDITOR.replace( 'body' );
// The "change" event is fired whenever a change is made in the editor.
editor.on( 'change', function( evt ) {
// getData() returns CKEditor's HTML content.
CKEDITOR.instances.insert_desc.setData( CKEDITOR.instances.body.getData());
});