How to remove non discountable amount from discount calculation in R12 AP

In R11, Oracle AP invoice has a field called Freight amount at the header level, we input in this field any amount that is not subject to discount. In R12, there is no such a field, anyone share how you record the non discountable amount would be much appreciated. I know there is freight line type at the line level but this is not applicable most time.

Thanks in advance