They have nothing to do with Eric introducing elements of a deal? (4,5)

'they have nothing to do' is the definition.
(idle hands means idle people)

'eric introducing elements of a deal?' is the wordplay.
'eric' becomes 'idle' (Monty Python member Eric Idle).
'introducing' says to put letters next to each other.
'elements of a deal?' becomes 'hands' (in card games, a dealer deals out hands).
'idle'+'hands'='IDLE HANDS'

'with' is the link.