Mapping

Hi Experts,

The interface i should design to communicate information regarding sub-rights invoices that are paid in SAP ERP(R/3) and the information fed back to from front end system (XXXXX)

I need to fetch the data like invoice number,value and amount paid.and send it back to some front end system. how should i design my interface?

Is there any idoc that i can use on R/3 side. if yes which idoc this fileds contains?

Appreciate if someone provides in detail

Please advise me

Thanks,