Dear Yoshi-san,
For a global company, e.g. COMPANY ABC (head office in the USA) has different legal entities in different countries (Japan, Singapore) where the local currencies are different. In my opinion below set up is normal.
Controlling Area ABC
Assuming all companies (ABC, DEF, GHI) are assigned to controlling area ABC.
Controlling area currency (for controlling area ABC) : USD
- COMPANY ABC (Head office)
Company code currency : USD
Object currency : USD
2. COMPANY DEF (Japan entity)
Company code currency : JPY
Object currency : JPY
3. COMPANY GHI (Singapore entity)
Company code currency : SGD
Object currency : SGD
Let say for Japan entity, a document of JPY100 (transaction currency or document currency) has been posted. The amount in company code currency is JPY100; amount in object currency will be JPY100; amount in controlling area currency will be USD0.99. (maintain exchange rate table: 100 JPY = 0.99 USD).
If another document of EUR100 (transaction currency or document currency) has been posted. Then the amount in company code currency is JPY 13,800 (maintain exchange rate table 1 EUR = 138 JPY; amount in object currency will be JPY 13,800; amount in controlling area currency will be USD136. (maintain exchange rate table: 1 EUR = 1.36 USD).
As for the third document of USD100 (transaction currency or document currency) has been posted. Then the amount in company code currency is JPY 10,100 (maintain exchange rate table 1 USD = 101 JPY; amount in object currency will be JPY 10,100; amount in controlling area currency will also be USD100, no translation is required.
Kind regards,
John Chin