Field help (BRDRUL) 

Explosion ruleRule that is used to specify how the invoicing elements from the original document are transferred to the destination document when the original document is partially selected on the destination document.1st order (shipment/invoice/credit note) :: The invoicing element is totally transferred to the first destination document.All the orders (shipments/invoices/credit notes) : The invoicing element is transferred to all the destination documents.Pro rata for the quantities : The invoicing element is split pro rata as a function of the quantity present in the destination documentation.Pro rata for the amounts : The invoicing element is split pro rata for the amount present in the destination document.