Below are the descriptions of the fields you asked.
REPID : Report from where the status originate
ROUTID : Subroutine of this above REPID from where the status originate
STAMID : Messag class whose message you are displaying as status in idoc
STAMQU : Status message qualifier
STAMNO : Status message number.
The above details can be seen in idoc status ->Sts Detail tab and Logging tab.
Function module IDOC_STATUS_WRITE_TO_DATABASE is the FM which writes the idoc status to EDIDS table.
Hope this helps.