Misappropriation setter concealed. 'Not entirely perfect?' That's outrageous! (3,4,4)

I believe the answer is:

the very idea

'outrageous' is the definition.
(I've seen this before)

I cannot understand how the rest of the clue works.

(Other definitions for the very idea that I've seen before include "that's absurd!" , "Well really" , "That's outrageous!" , "No way" .)

I've seen this clue in The Everyman puzzle in The Observer.

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