Link between user-id and user name

unknown

Trying to create a report to show user that made tax marital status changes as we are going live with ESS and HR anticipates getting phone calls from employees i.e. "I didn't change my exemptions". The change detail prints beautifully on the PR280 Deduction Audit report, however, the "Change by" field contains the internal user # i.e. NT00000001. What table/field/link do I use to see to write a report that shows the change was made by "Mary Smith"?

plancor

If the change was made through ESS, the Changed By user is "W" and their employee ID number.