On the Income Statement, the same Concept is used for sales from products and services, but differentiated with a unique member per the 2018 US GAAP Taxonomy requirements (same goes for Cost of Sales) to avoid a duplicate fact error. However, you cannot use a concept more than once in an XBRL calculation assertion. For presentation purposes, the same concept is being used for the two XBRL calculation assertion contributors. How does one apply a calculation assertion when for XBRL in this scenario? See illustration below.