I am also looking for this, and the reply from Quickbooks is zero helpful. Disappointed. The transaction split report is great, but not useful because I am looking for a report that I can easily calculate how much of our expenses each month are billable versus not billable. It's key for our business to be able to see the general numbers, and also to double check that we aren't missing anything. 

As it is currently, no matter how I manipulate this report, I am unable to get this information without exporting to excel, and spending ALOT of time removing the duplicate amounts. If I leave the Accounts Payable Account in, it will show me billable labels in the billable column (yes), but if I remove the Accounts Payable account through customization, it removes the label in the Billable column, thereby removing any point of me running this report.

Frustrating.