Aloofness of France’s top couturier turning over his cash (8)

'aloofness' is the definition.
I don't know anything about this answer so I can't tell whether it can be defined by this definition.

'france's top couturier turning over his cash' is the wordplay.
'top' says to take the initial letters (in a down clue, the first letter is top).
'couturier' becomes 'Dior' (Christian Dior, luxury fashion house).
'turning over' shows that the letters should be reversed in order.
'his cash' becomes 'eur' (I can't justify this - if you can you should believe this answer much more).
The first letter of 'frances' is 'f'.
'dior' back-to-front is 'roid'.
'f'+'roid'+'eur'='FROIDEUR'

'of' is the link.

Can you help me to learn more?