Reporting country EGMLD in Substitution/IDoc

Hi to all,

we make some FB01 postings via IDoc.

We need also to fill out the VAT reg. number BSEG-STCEG. This number is derived based on the reporting country, which has to be filled out within the line item additional data (BSEZ-EGMLD).

Is it possible to enter the reporting country automatically:

• via IDOc - if yes, which segment?
• or via FI substitution? - within substitution, structure BSEZ is not available
• or via an user exit?

Thanks a lot for all inputs.

Regards

P.