What currency do they spend in Indonesia?
Indonesian rupiah
The rupiah (Rp) is the official currency of Indonesia. Issued and controlled by the Bank of Indonesia, the ISO 4217 currency code for the Indonesian rupiah is IDR. The name "Rupiah" is derived from the Indian word rupiya (रुपीया), ultimately from Sanskrit rupyakam (रूप्यकम्; silver). Informally, Indonesians also use the word "perak" ("silver" in Indonesian) in referring to rupiah. The rupiah is subdivided into 100 sen, although inflation has rendered all coins and banknotes denominated in sen obsolete.
Indonesian rupiah
The rupiah has been subject to high inflation for most of its existence (which as an internationally recognised currency should be dated to 1950). Various attempts have been made to maintain the value of the currency, but all were abandoned.