Add columns or Flexfield information to Drill Down Accounts in Reports Manager

Dear experts,

We are currently working with EBS R12.1 and we are using Reports Manager to run a custom report. This report provides account balances information and integrates them into a summarized final layout.

We run the Generic FSG Drill Template with a defined period, afterwards we click on any Group of Accounts in the left so Drill Account Balances Window pop-up:

We need to add a column in the window Drill All Account Balances in order to give more information of the Account, like Account description or name of the segments

If it is possible, how can we achieve this task? Moreover, if there is a flexfield option to add it, what's the flexfield name?