Crystal Reports Record selection IF Statement

Message

     HI,

I am trying to use the following formula in a record selection.

(IF {TABLE.DOCUMENT_TYPE} = 'REBILL' AND 
{TABLE.DOCUMENT_TYPE} = 'INVOICE' THEN
{TABLE.DOCUMENT_TYPE} = 'REBILL' ELSE 
{TABLE.DOCUMENT_TYPE} = 'INVOICE')

When there are multiple records with the same invoice number but a different document type, I would like it to pull the REBILL document type instead.

With the IF statment I have written, only the document type of INVOICE is pulled when a REBILL is present.  

Can anyone see what I am doing incorrectly?

Thanks,
Matt