Balancing Segment from Item Exp for Tax Account

Hi eTax Experts,

We have over 20 companies (balancing segment in Oracle Accounting Flexfields) within 1 Operating Unit in AP. When user enters invoice expenses, it can be charged to multiple lines with different companies values on the Distribution Charge Account.  However, the GST/Tax Account is defaulted to only one specific Company value from Tax Rate setup.

Requirement is to have each tax line dynamically use the balancing segment from the Item Expense line. For example:-

Company ABC - Expense Line   $100

Company XYZ - Expense Line   $200

Company EFG - Expense Line    $300

Company ABC - GST (Tax Line) $60 ===> require this line to split to 3 Tax Line as per expense lines above