Topside in general means not in the general ledger detail / done at a higher level. Sometimes has a negative connotation as they can used to manipulate results as the "topside" nature puts it outside of most organizations internal controls. Sometimes used to record/adjust entries that were made earlier but new data dictates a change before releasing statements. Also a way of keeping certain information private in an organization as the Controller/CFO maintains control of data not available to others (i.e. size of bonus/legal/tax/bad debt accruals/reserves).