Money Changer

My Bali ESP trip is coming up soon and I have yet to change Indonesian rupiahs. I thought I could get the girls' father to do so at the bank he is working at. But it seemed the banks don't sell and buy Indonesian rupiahs. Thank goodness, my father is home. :) He helped me to change S$250 into Indonesian rupiahs at the money changer.
This is the first time I have seen Indonesian rupiahs. Goodness, the notes are of such big denomination, e.g. Rp10,000 and Rp100,000. I have never seen so many zeros on a banknote. Hope I don't make mistakes when paying and receiving back change in Bali.