If your overstay in Bali is less than 60 days, you must pay a fee of IDR 300,000 (~US$ 21) for each day. The payment for overstay – is not a bribe but a legitimate non-tax state revenue. The overstay up to 60 days is an administrative violation.
However, overstay of more than 60 days is a crime according to the Indonesian law., the immigration will investigate you very thoroughly. Consequently, you will be deported from Bali and blacklisted from entering Indonesia for a certain period. Read more