Document Types in Intercompany Elimination 
A document type for carrying out intercompany elimination has to be entered in the Implementation Guide in the section Posting. The document type has to have posting level 2.
Posting level 2 says that the posting should be carried out in pairs for the companies. This means that only one company pair can appear within any single document. When you are evaluating a subgroup, the total records for the elimination posting are only included when both companies in this company pair belong to the selected subgroup, and you perform a purchase method (full) consolidation or a proportional consolidation. If one of these conditions is not met, then the total record concerned cannot be evaluated. In this way, you can guarantee that the group eliminations only have to be carried out once for the entire consolidated group, and that all elimination transactions for any subgroups are automatically carried out.