Excessive documentation returned, leading to more of the same (5)
I believe the answer is:
ditto
'more of the same' is the definition.
(I've seen this in another clue)
'excessive documentation returned' is the wordplay.
'excessive' becomes 'ott' (abbreviation for 'over the top').
'documentation' becomes 'ID' (identification documents).
'returned' says the letters should be written backwards.
'ott'+'id'='ottid'
'ottid' reversed gives 'DITTO'.
'leading to' is the link.
(Other definitions for ditto that I've seen before include "In lists, the same again with two small marks" , "Repeat the word above" , "Same again, indicated by two dots" , "Mark used to indicate the word above it should be repeated" , "Do alternative" .)